Socket 7 motherboard repair - endless faults!

[@adriansdigitalbasement]

It freaking works!!! Great video! 👍 The bad cache chips certainly took out the voltage regulator transistor too.

[@tony359]

So happy to see you here Adrian, I love your videos! Thank you so much for watching and for your kind words!

[@DjMarik78]

@tony359 that transistor is 2SD882 ( the "Y" is just for current amplification classification ). It's just your basic TO126 medium power NPN transistor, there are many replacements for it ( BD175, BD435, BD437, BD439, BD441, etc... ). You do not always need to find the exact part number for replacements when it comes to transistors, you just need to make sure the replacement one has: - Enough VCEO, meaning voltage rating ( higher than the input voltage from the power supply, at least twice i should say ). - Enough IC ( current rating ), at least the same as the faulty transistor ( higher is almost always ok ). - At least the same hfe class as the faulty transistor ( higher is anytime better ), if possible always choose the one with -16 suffix, it is a higher hfe class, thus you make sure you are ok at this aspect. Always use parametric search on the main parts distributors ( as Digikey, Mouser, Farnell, TME... ). Any other parameter shouldn't ruin your day.

[@tony359]

This is incredibly useful, thanks! I'll definitely save this for future use!

[@CallumFaulds1]

I came back just to watch this classic of your channel! Excellent troubleshooting and repair work. We can all learn a thing or two by watching your videos.

[@tony359]

ahah indeed it's where everything started! I agree it's a cool video, lots of things happened there! Thanks for coming back! :)

[@radionicretrofit]

Tony, as an old subscriber since vogons it is nice to see how your channel grows and improved quality. Keep it up! We need more retro content such as 486 systems.

[@tony359]

I've run out of retro boards to repair! :D Thank you for watching and for your kind words!

[@juliedunken1150]

@@tony359 buy more, simple as that

[@tony359]

@@juliedunken1150 ahaha - I'm always trying of course! (spoiler: I just got another one for a future video! ;) )

[@computerguy096]

I'm glad you found The Retro Web project useful, even if, in this case, the board is barely documented. We're always looking to improve the info on them. You've also earned a new subscriber, looking forward to more x86 hardware repairs :) Kind regards from the TRW team.

[@tony359]

Oh TRW is a valuable source of information - not sure how the Internet could exist without it! Thanks for watching and for subscribing, I look forward to contributing more to the database!

[@Malheirods]

Thank you for your hard work !

[@MarcoGPUtuber]

Hi. I have a couple of obscure boards myself. If I want to contribute, should I post pictures in its original state or after I recap them?

[@Shmbler]

I fixed a badly damaged socket 7 board from a box of junk just yesterday. The process was major fun once again and it was so rewarding to see it booting up again, even though I probably won't ever actually use it. Two weeks ago I fixed a badly corroded socket 7 board from a different box: Detached Vcore MosFET (corrosion), a bunch of detached legs on a PB cache chip (also corrosion) and a tiny speck of impact damage that cut a trace on the back side under the CPU socket, which manifested itself by only the first POST code popping up occasionally :-)

[@tony359]

I'll never use this board either - but we both know the feeling when they come back to life after many hours of work! :)

[@Dmitriy_Emelyanov]

Thank you very much! Your video inspired me to find broken place on my 7-socket motherboard and now it works again! Please continue to tell about motherboard repairing

[@tony359]

that's amazing! Well done! and thanks for watching!

[@blakecasimir]

Just discovered you. Great editing, thorough process, tons of info, very clear mic recording. Subscribed! Keep up the great work, sir.

[@tony359]

I am very happy you enjoyed the video and let me thank you a lot for your kind words! Indeed recording and editing those videos is a big task (getting better but still takes many days of work!) so comments like yours are very much welcome! Thanks for watching and for subscribing!

[@blakecasimir]

@@tony359 The effort shows, imho. 👍🏻

[@edwardmacnab354]

Best demonstration of a piece of junk I ever watched . Your expertise , however , is awe inspiring !

[@tony359]

That is very kind of you to say, thank you!

[@Thorsten369]

What you do was my old job from the late 90's. Did repair all kind of mainboards brands like Asus, MSI and yes even Abit and Aopen back then, always loved my job and i'm glad to see that some people like you working on some older mainboards. Keep up the good work Tony.

[@tony359]

Amazing! Thank you for your kind words and for watching!

[@necro_ware]

Great video and very exciting research! And of course congratulations to the 1000s subscriber!

[@tony359]

Thanks for watching, Master! Your padawan is excited to have you here! :)

[@necro_ware]

@@tony359 Oh, I please you... :D

[@ismail3404]

wow two master here

[@034G63EVO]

I am a Tech. I have ALWAYS wanted to be at this hardware level, having the tools and knowledge to make repairs such as this. You have a new sub sir.

[@tony359]

Thank you a lot!

[@JohnnyUtah488]

There's something so oddly satisfying about these retro repair videos. Great job!

[@tony359]

Eh eh I very much understand! Thanks for watching!

[@iprofessionals_india]

very informative Tony. Keep it up.

[@tony359]

Thank you!

[@ted-b]

Great work Tony! Wow, what a rabbit hole!

[@hashemmi24]

I love how the video is soo involving, when you count i get excited to see what will pop up ! PURE QUALITY

[@tony359]

Thank you Hashem, it's very kind of you to say. I'm confident that one of these days I'll have some magic smoke coming out at the "three" :) Thanks for watching!

[@hashemmi24]

@@tony359 Thank you for all the knowledge you already shared. i will be binge watching them.

[@tony359]

@@hashemmi24 That is so kind of you, thank you! Please bear in mind that this channel is young so the older the videos, the... less polished they are (and some are very long!) :)

[@kargandarr]

I have seen AT and ATX motherboards and this one appears to be one of the several hybrid models from the transition period between the two formats.

[@tony359]

Interesting! Those were fast moving times when it come to computer tech! Thanks for watching!

[@andream1977]

A spectacular video, well done and full of information. Congratulations Tony!

[@tony359]

Thank you Doc! 🖖

[@devil5051000]

Have seen several boards with faulty PS/2 memory slots in the past. This metallic clamps wear out and no longer provide enough force for the memory modules to make secure contact. So the system is not running at all or freezes as soon as the memory starts to warm up. Or the size of memory is halved after starting the computer. You can replace the sockets or simply switch to the SD-RAM sockets next to them. It is very convenient that more recent socket 7 boards already have them.

[@tony359]

Yes, I've noticed that some of those older sockets tend to fail to hold the module in place. I had to bend some of those clips in the past to allow the modules to click in place. Thanks for watching!

[@LeeMc007]

What an excellent video from the editing to the commentary and I also enjoyed your diagnostic process, I think you only tripped yourself up being overly careful with that transistor and there's nothing wrong with that. Subbed and looking through your other uploads to see what I've been missing, congrats on the subs you will surely get lots.more making content like this. 👍👍

[@tony359]

Thank you a lot for your kind words, and thanks for subscribing!

[@kamikazekk-df4vz]

Congrats very good job, sometimes the lesson number one to remember is never give up.

[@tony359]

Thank you!

[@thereallantesh]

Great video. This is the first time I've seen your channel, and I love it. Count me in as a new subscriber.

[@tony359]

Thank you for watching and for your kind words!

[@mikebarushok5361]

Reminds me of a Gigabyte motherboard that I was setting up for a customer (as a new build). Except it had a progressive series of cascading faults. Within 30 minutes it completely failed to post but damaged the cpu and ram, so the shop I was working for only got the ram and mobo replaced under warranty. We took a slightly different model mobo, but lost money on the cpu and excessive labor

[@tony359]

Wow! I was lucky that all the voltages on my board failed by lowering their values! Someone on Vogons suggested to use a CPU which uses the highest possible voltages when testing a board. I don't have one yet and as you noticed testing the voltages beforehand is not always a reliable test! :) Thanks for watching!

[@swilk]

Wow, that MB looks exactly like my first motherboard! Only difference is that mine did not have any cache installed. I don't remember the model and it was a no name product, but looks the same. Thanks for a nostalgic moment!

[@tony359]

glad that the video had that effect, which I know very well! Thanks for watching!

[@tefatronix]

Looking at the cache chip labeling, the "6432" near the end might indicate those are classic 64k x 32 data lines SRAMs. I just took a look at some Socket 7 MBs with similar cache organization I have here and found these chip numbers: UT6164C32Q-7, or T35L6432A-6Q (2 chips 64kx32, so 512kB as you have), or W25P010AF on a 256kB cache MB (some changes might be needed to run with 32kx32 chips). IIRC the pinouts of these chips with the same size/organization are mostly the same, but I'd measure VCC/GND pins just to be sure. Due to the CPU having a 64 bit wide data bus, it won't work with just one chip, and even if those were 64kx64 or 32kx64 chips, etc., it might need reconfiguration of some resistors. But the same applies when changing chips to smaller size, e.g. 64kx32 to 32kx32. Little story, I have a FIC VA-503+ which had faulty cache, but with two 64kx64 chips, so I removed one chip, found a photo of the version with just one chip (512 kB) to determine which one I can remove and which resistor positions to change, reconfigured 0R jumpers/resistors according to the photo, still not working - swapped the chips again and voila! Much less performance hit from having half the cache vs 0 cache!

[@tony359]

Thank you for the comprehensive analysis, it’s so cool to understand those things. Meanwhile I have found some replacement so watch this space for a follow up!

[@tommyb.6064]

new to this chanel, very interesting. I want to get into SMD repairs eventually... and also back to non smd stuff, it's been a while i havent put my knowledge to good use... but your channel seems to be the perfect school for that. thanks for sharing.

[@tony359]

Thanks for watching!

[@muharemjusufi5542]

Great Job Tony. Subscribed. Timestamp @20:22: Maybe there is a broken trace (pin4)

[@tony359]

Thank you for watching and for the feedback! Do you mean that white line you see on the video? If that is what you mean, those are white marks printed on the board every 10 pins - so you don't lose count when looking for a specific number. I had a look under the microscope anyways and I do not see issues there. But thank you anyways, 4 eyes are always better than 2! :)

[@JonathanBastienFiliatrault]

At 25:39 I can see that one of the toroidal inductor cores is cracked into many pieces. It might cause the power rails to go wonky.

[@tony359]

Good eyes, others have noted too. I had some footage about that but in the end decided not to add it to keep the video shorter! Thanks for watching!

[@SianaGearz]

Oof great partial repair. For sure has to be a cascade failure where one failed component then causes the rest to fail. Beats me in what order this all happened though, i suppose the FET could have been at fault sending a bit of a higher voltage jolt to 3v3 components, which didn't take it kindly. Hit my head on the desk though when i saw you not connecting the E leg of the replacement FET. For the reason that you found out.

[@tony359]

Eheh yes, il always learning when it comes to electronics. But at least I realised my mistake! Thanks for watching!

[@mahmoodsaraf1]

Very good video, thanks Tony.

[@tony359]

Thank you for watching!

[@jeremiefaucher-goulet3365]

I've discovered your channel thanks to this video. Loved it so I subscribed. Now going to look at your other videos....

[@tony359]

Thank you Jérémie for your kind words! Welcome!

[@rimmersbryggeri]

I think i may have had this motherboard back in the day. If so it's an eaglemax branded board, they were very much into the at+atx thing. Here in sweden they were directly imported by chinese shop owners. Was difficult to find any documentation back in theday to. Mine had integrated graphics but might have been newer than this since i had a K6 2 400mhz in it. I think there was alo a brand called Jetway that was simular.

[@tony359]

PC-Chips were apparently very popular back in the days - some were good, some were not :) Thanks for watching!

[@krz8888888]

Thanks for saving the board, looks very similar to the one from my first computer

[@tony359]

Thanks for watching!

[@mikemanning998]

Wow, very impressive work. I have seen some of your other videos where you "magically" re-solder components, not to mention your overall skill set in diagnosing mother boards etc. New subscriber here, starting to appreciate the older computers more every day, because of all the spyware and viruses infecting the newer models. I am seeking parts to assemble a Windows 98 Gaming PC. If you are selling or if anyone seeing this is selling, let me know! I need 2 PC's, one for my wife and one for myself.

[@tony359]

Thank you! I'm glad you like my magic skills! :) I shall post something here if I ever sold something - I honestly don't need all those Socket 7 motherboards! :) Thanks for watching!

[@ThomasShaneHynes]

Nice video man, keep up the good work you're smashing it!

[@tony359]

Thank you!

[@helifynoe9930]

My 2009 LENOVO M58p had just started doing the boot loops. Oh no, I thought. But I managed to get it up and going once I had replaced a bad electrolytic capacitor in the 280W PSU. It may be an old computer, but it is still fast enough to handle 1080 60fps videos for both Netflix and KZbin. Being so old, it also only cost $27 to upgrade the CPU. LOL

[@tony359]

Amazing! Yes I like how you can now get those once-very-expensive-upgrades for peanuts!

[@helifynoe9930]

@@tony359 Yes, I wanted to keep this computer going as long as possible, so I even added a couple of fans. There is one chip on the mother board that has a heatsink, but it still gets darn hot, so I extracted a tiny fan from an old dead Pentium module, and used that to keep things cool. The other fan is positioned on the front of the desktop chassis, and thus it helps with the overall air flow going through. The amount of dust that its blades quickly accumulate, tells you it is doing it job very well. I also added a fan to my 2009 SAMSUNG TV, and that made a huge difference to its overall operating temperature. This TV died at one point earlier on, but once again, all I had to do was replace one measly electrolytic capacitor. I may be an old timer at 65 years old, but I still get a kick out of fixing things like those mentioned, plus my 2004 microwave oven, and my 15 year old coffee maker, my 1987 DENON DCD-900 CD player, my 1978 home made speakers that each have one 15" woofer, 2 mid-range drivers, and 4 tweeters, my 1976 Heathkit AA-1506 audio amplifier that at one point went up in smoke, my 2008 Sony headphones, and a few other odds and ends. Saves money, and givers me something to do. Anyhow, Thanks for making a great video.

[@BoBaH_BoBaHoB]

I like early boards with PCI32 bus. I used to run VXWorks on that boards. I could use PCI RTL8139 for networking. And 16 Mb of RAM as required by that RTOS. And X server too.

[@BoBaH_BoBaHoB]

And I like Pentiums because they are superscalar and much faster than 486.

[@RajA-tx5zr]

Nice explanation and step by step inspection..

[@tony359]

Thank you!

[@pa-vl1kg]

What a job. You got a new subscriber sir.

[@tony359]

Thank you!

[@andrewdoherty737]

That looks like the Mitak boards we used to use in circ.2000

[@gnif]

to remove the enamel off copper wire (magnet wire) a flame is usually used, any old lighter works well.

[@tony359]

Thank you. I think I tried that but ended up with a burnt copper wire? I’ll try again. Thanks for watching.

[@gnif]

@@tony359 No worries mate. I would however suggest that you have look at Kynar wire (not the cheap knockoff stuff) for this kind of repair in future. If you must however use magnet wire be sure to remove the enamel before trying to solder it down, the extra unnecessary heat on the fine PCB traces can cause the traces to lift off the fibreglass subtrate causing further damage.

[@tony359]

@@gnif You are totally right about heating traces, that is why I was disappointed about the outcome! I tried flame and soldering the wires before using them (require 400C apparently) but nothing gives me a clean result. Kynar wire is excellent but it's not available in small gauge. I'll keep researching and testing, thanks for your input!

[@Hereford1642]

@@tony359 Some flexible audio cables are actually multi stranded fine copper wires inside. Or maybe event the teased out screen wire would suit your purpose. Then you would not have enamel to remove.

[@tony359]

@@Hereford1642 I know which ones you mean, they have very very fine strands. I can try again for sure. Thanks for mentioning!

[@tomwaller6893]

Cool, great job. Such skill with no documentation.

[@tony359]

Thank you a lot! :)

[@jameskidd7906]

Yes sir i understand thank for the share

[@Epictronics1]

Just found your channel. Great MOBO repair : )

[@tony359]

Thank you Sir, your channel is amongst my favourites, looking forward to your next videos!!

[@Epictronics1]

@@tony359 Thank you : ) Next video is out tomorrow : )

[@jimviau327]

04:53 According to Datasheet the jumpers should be CLOSE OPEN CLOSE CLOSE OPEN, ( ground floating ground ground floating) , hence 3 jumpers, contrary to what you mentioned which is going to give 1.4V, or I really need more coffee 🤔

[@tony359]

That is very right, well spotted! Took me a few hours to realise, I put a subtitle at 5:09 to clarify! Thanks for watching!

[@bsvdoom]

It was my first PC, and i decided to repair it, no luck, then you came, like a christmas present. Very nice video, thank you! I am stuck at error code 05 at 31:00, where did you get the it8687r keyboard controller chip from?

[@tony359]

From eBay UK, it was a UK seller. Pricey if I remember right. Did you check the legs? Thanks for watching!

[@bsvdoom]

Yep, pricy, fould some cheap on ali, but I wont try those. Ill look ebay, thanks. Yes, Ive checked all issues what you sorted out in your video. I got thinking, it has a 24/48MHz clock generator, myb its worth checking if the clock is correct, I hope it can be supplied from outside if its faulty, but I dont have an oscilloscope so can not check it.meh. The following pins sould be interesting by the datasheet: 7 CLKOUT O8 Output clock generated by the crystal oscillator 8 X2 O Crystal oscillator output 9 X1 I Crystal oscillator input 48 MODE IS Primary function is selected when this pin is low; secondary function is selected when it is high

[@tony359]

@@bsvdoom interesting analysis. I didn't check on mine as it was scorching hot - so likely failed.

[@bsvdoom]

@@tony359 yep, mine is not hot so got my hope's up

[@dumyyyyyy]

I saw old pentium II board type vertical cpu that have this kind of cache on it. Also on old video cards the video memory have that format.

[@tony359]

Thank you! One of my viewer managed to send me a set from another TX board so watch this space as I'll try to fully restore that board!

[@guilopur]

Hey Tony you just got another subscriber, great video.

[@tony359]

Thank you Hector!

[@Roadkill7878]

Great problem solving

[@tony359]

Hey Thank you! I have to admit that this one was a challenging (=fun) one! :)

[@Pulverrostmannen]

I was like no please no it won´t work when you lifted the emitter of the transistor to test it so I was also happy when you figure out it needed the feedback to work. it is likely the current were so high in those cache chips it burned out that transistor for that reason. mobos are pretty complex to repair so well done so far

[@tony359]

Thank you!

[@emplp]

Used to have a lot of ITE chips go bad on motherboards in megatouch countertops

[@anshtoN]

Thank You so much I have been trying to crack it since 2 days.. Finally it worked.. thanks

[@tony359]

amazing, thanks for watching!

[@SLeslie]

If you miss the initialization period turning on the external 3.3V power supply, the components fed by the 3.3V circuit might stay uninitialized and that could explain the no boot behaviour.

[@tony359]

That makes sense, thanks!

[@lepompier132]

That board falls in the in between generational board and is probably a clone of a well known clone MB. That is why sometime it's hard to find manuals or drivers for some of these boards. Now this board may be in reality a P55C board with added features vs it's original counterparts from Gigabytes, Asus just to name a few. And often they have these brand names: AOpen, Acer, PC Chips, QDI, Lucky Star, etc So next time you find a board that looks unknown, usually the part number will give you clues of where it was copied from. Like mentioned with this board, ATX55C could be in reality an hybrid of P55C. Hope this info will help in the future. I forgot one thing. When searching info for a MB. Sometime you can get more information in your search if you ask the right question. In your case you could have found all MB manufacturer for Socket 7 MB and you would have found who make your board.

[@tony359]

It does thanks! You’re not the first mentioning the P55C which I’m not familiar with. I shall do some research! Thanks for watching!

[@Caleb-fv5fp]

Socket 7 is my favorite era

[@maxtornogood]

Starting the battery of tests.....by testing the battery 😝 Good to see the board at least *freakin'* working as someone with a digital basement would say! 😉

[@tony359]

ahah you know what, I didn't realise I said that! Thanks for watching! :)

[@Flavius-Tech]

Have someone noticed those caps and resistors how beautiful they are soldered?

[@sebastian19745]

I see that the motherboard have an ATX power connector. Did you checked that by any chance the board can draw 3.3V from the ATX power and not making it onboard like when powered from an AT power? I am also curious what is doing the mobo wit the 3v3 rail from ATX power connector.

[@tony359]

Good point! I checked and they seem to be disconnected. I do not see any traces coming out of the 3.3V lines and I cannot measure continuity with anything. Another board I have have a jumper selection to be used for when ATX is being used - this one I am not sure as I do not have the manual. There is an ATX switch jumper and that's it.

[@sebastian19745]

@@tony359 Thank you. You know, I find fascinating the computers from transition periods. When I upgraded from 486 to Pentium, I also upgraded from AT to ATX without knowing it. Imagine my surprise not seeing "Now is safe to turn off your PC" message. Also is interesting to see what approach took the manufacturer to integrate old and new technology (SDRAM and FPM/EDO RAM in your case). That is why I was intrigued about 3v3 power rail. Also I find weird the thing that ATX dropped -5V that is needed for some ISA cards and is used on a ISA machine.

[@tony359]

@@sebastian19745 it was an interesting period indeed! Things were changing so rapidly and computers were fully obsolete every 24 months more or less! :)

[@adamcarver9057]

By chance do you know the name of that green tool you used to remove the solder mask?

[@tony359]

Yes it was recommended by Necroware. I got it from aliexpress but the one I got is not available anymore. I found another one which looks like the one I have (can’t guarantee it’s the same) and you can find it here: www.aliexpress.com/item/1005004052040884.html Thanks for watching!

[@adamcarver9057]

@@tony359 Thanks for the reply, these won't work on the battery hand drills I have but they are still supper useful.

[@sectokia1909]

Try moving the remaining cache chip to the other side, and then opening that soldered jumper.

[@kostasvarsamis4155]

excellent video. but.. what do u think caused those multiplied faults? i coulnt be the damaged tracks,cause they were created from some1 that tried to remove the board.means,no power while scratching the tracks so there has to be something else that created all those problems. could it be a bad PSU? personally,i dont think so.cause almost all computer PSU will shutdown if any of their output voltages are too high/low. so, whats your opinion?

[@tony359]

Good question. I feel the 3.3V power transistor damaged the cache modules with a spike - then it just dropped to 2.2V as to say "it wasn't me". But the RS232 buffer chip is 5V so... What if there was a 5V spike from the PSU, that damaged the RS232 chip, the 3.3V power transistor which in turn brought down the cache. Potentially RAM, CPU and anything plugged into that motherboard went. Then the motherboard was binned and got physically damaged. PSU are normally protecting the outputs but anything can happen (particularly on cheap ones...). What do you think? Thanks for wathing!

[@un4gs601]

Very nice video !! One question: How did you find the connection between transistor and ram pin do you have schematics or by testing or there are books on these ? Thanks

[@tony359]

Thanks for your comment! Well I knew the PSU didn’t output 3.3V so it had to come from somewhere else. The CPU switching supply is variable so can’t be that one. That transistor looked like the only component suitable to be used as power supply so I checked continuity from the 3.3V supply of the ram (you can find pinouts online) and the transistor.

[@DavidScheiber]

Apparently powering the cache and similar ram chips without "initializing" or doing anything with them can put them in a "locked up" state and cause them to pull excessive current and eventually overheat.

[@tony359]

That makes sense and explain why on misbehaving systems sometimes working CPUs get scorching hot if they're not being initialised! Interesting, thanks!

[@budhimulyawanrachmat3327]

I'm interesting with you test device at 24:38, what is it and where I can get one?

[@tony359]

Hello - I got it ages ago. You’ll find many different models, they’re based on Arduino if not mistaken. I wouldn’t be able to say which one is the best one today (maybe one which is upgradable?) but it you Google for Arduino component tester you can find them cheap. It’s honestly super-useful but don’t do as I did and check a large capacitor still charged! 😂 thanks for watching!

[@budhimulyawanrachmat3327]

@@tony359 Thank you for the information, I appreciate it 👍🏻

[@johnf4085]

Bravo. A lot to learn here.

[@tony359]

Thank you!

[@Bushuu]

I assume you have checked in the bios as some systems would allow you to enable/disable cache.

[@tony359]

I have - also tried disabling/enabling it but unfortunately it made no difference. Thanks for watching!

[@DavidAmorimNascimento]

Amazing... Big hugh from Brasil!

[@tony359]

Old video but always nice to watch! Thanks for watching, obrigado!

[@elenium115]

What resistor you are using for testing this transistor? The one you put between ground and emiter.

[@tony359]

It’s an 8 ohm 100W one. Totally overkilled but it’s handy to use - I use those for testing amplifiers . I use ohms law to make sure that that’s going to be ok. 4V and 8ohm make 2W or 500mA.

[@elenium115]

@@tony359 Thank you. I wonder why you want to put a load on this transistor :) many times I do the same check but never put a load on transistor :)

[@tony359]

@@elenium115 Sometimes a supply voltage can be off if there is no load. Check on my other video here kzbin.info/www/bejne/Z5y5oaZopKegntU what happened when I tested the CPU VCC with no load! :) In this case the load was not the issue but I thought it could help.

[@elenium115]

@@tony359 Ok thank you for link.

[@clivewright7778]

Bro I love the way u troubleshoot. Where were u all this time ? 👍

[@tony359]

Ahah thank you!

[@Neksus-M06]

Can't you figure which lines go from cache to any resistor around (on the good cache board) in order to set the size and see if it works on this board? Compare and fix? Interesting video, thanks.

[@tony359]

I tried yesterday night! The "selection resistor" (at least the one I think it is) seems to go to multiple pins on a chip so it's not easy to figure things out. I'd like to try sourcing new modules first, they are not so expensive. Failing that I'll think of something - a MB like that with no cache is no use to be honest... Thanks for suggesting!

[@nm0490]

How do you know which CPU pin to check if the voltage is correct? From the CPU datasheet? If so, where can I find such schematics?

[@tony359]

For socket 7 this is the page I found more useful: www.pchardwarelinks.com/586pin.htm Please note the companion page where each pin is described, the link is on the same page. The pinout are when looking from the bottom of the board. For voltage you can use one of the many VCC2 or VCC3 on the board. A graphical visualisation of the voltage pins is pretty clear on this page: en.wikichip.org/wiki/File:CPGA-321_K6-2_pinmap.svg I hope this helps and thanks for watching!

[@jodycwilliams]

Keyboard chips dying back then would prevent boots on a lot of MBs. I know I personally ran into that issue in the mid 90s a few times.

[@tony359]

Cool! I thought they would throw an error message, not preventing the whole board to post! Thanks for watching!

[@eugenioarpayoglou]

There were a bunch of motherboards (mostly PC Chips brand) that came with fake cache chips soldered to the board. I don't know if that's the case for this mobo.

[@tony359]

Really! I wouldn't be surprised then! Wondering whether replacing those fake chips with real ones would enable the cache or whether the whole PCB was just not designed for cache!

[@mikebarushok5361]

I believe most of those mother boards didn't have any traces connecting the fake chips to anything except grounds.

[@Games_Benchmarks1979]

Is this what you do fix motherboards and other computer components because I have a msi x99 sli plus motherboard that is dead and need repair

[@tony359]

Well the X99 is a much modern board and it’s much more complex than a 1996 Socket 7 motherboard!

[@m8hackr60]

Tony, new subscriber here. Great content. Loving this stuff. Just curious, is there a significance to the number 359 in the channel name?

[@tony359]

Hey thank you! Regarding the name, yes! :) I might reveal that one day! Thanks for watching!

[@train4905]

Exellent job sir,well done

[@tony359]

Thank you!

[@ALLMIGHT_PLUS_ULTRA]

Hoping you will start repairing HDMI or DSP issues for AV receivers, it is VERY common issue but somehow nobody is making videos of them the same detail as you.

[@tony359]

who knows, maybe one day! This is "tinkering shop", anything can happen! Thanks for watching!

[@ALLMIGHT_PLUS_ULTRA]

Wow thanks. :D 🙏

[@madyogi6164]

Very, very impressive!

[@tony359]

Thank you!

[@WinrichNaujoks]

Nice video, but doesn't need background music.

[@8o86]

love the curved traces

[@tony359]

Ahah yes they look so cool!

[@gerrepair7862]

I love this retro repairs.👍 I repair only graphic cards.

[@tony359]

Thank you! New or old graphic cards?

[@gerrepair7862]

@@tony359 only newer card. From gtx9xx to RTX30xx cards. I never worked on old cards.

[@tony359]

@@gerrepair7862 on my stack of ‘broken things to repair’ I have an R9 270 which… works on some systems and not on others, powers up intermittently and funny things like that. I found a shorted cap which I replaced (the board still managed to power up and work with that though!) and that surprisingly didn’t improve things. Weird. I was thinking of reflowing it at some point but I couldn’t replicate the issue anymore last time I tested it 😂

[@tony359]

@@gerrepair7862 on my stack of ‘broken things to repair’ I have an R9 270 which… works on some systems and not on others, powers up intermittently and funny things like that. I found a shorted cap which I replaced (the board still managed to power up and work with that though!) and that surprisingly didn’t improve things. Weird. I was thinking of reflowing it at some point but I couldn’t replicate the issue anymore last time I tested it 😂

[@gerrepair7862]

@@tony359 I only repair nvidia ,for a got reason😅. The r9 270 has sometimes Problem with the GPU soldering. The question is ,it is the the connection from DIE to pcb DIE or is the connection between pcb DIE to card pcb bad. When you have problems with the card on some mainboard and one some not, check always the pex voltage and the pcie caps.

[@tfhhjh3372]

very good channel I have the same motherboard, I donated it to the person who was about to throw it away. I would like what equipment do I need to check status? thank you

[@tony359]

Hola! Well, you need a power supply, some RAM, a CPU and a video card! Good luck!

[@GabrielZ666]

Necroware: "Hold my beer..." 😆

[@GabrielZ666]

Finished the video, what an amazing troubleshooting skill and also a superb set of tools! I think those similar chips from the Vogons thread will work, looking forward to the next episode!!

[@tony359]

@@GabrielZ666 Thank you! You make me blush! I don't think I could find those chips either so I am trying to get some I have on a similar motherboard, UM61L3264F-6. Who knows 1. if they work 2. if they are genuine 3. if I ever receive them! :) Watch this space! :)

[@christopherjackson2157]

Amazing repair

[@tony359]

Thank you!

[@spicybecca4899]

Lovely video!

[@tony359]

Thank you!

[@santiagoarasanz]

You are great Tony, 1+ follower

[@tony359]

Thank you very much!

[@old486whizz]

1024+1 subscribers!! You got a digital thousand!

[@tony359]

The video where everything started! :) That was a fun repair! Thanks for watching!

[@old486whizz]

Oh sorry Tony, didn't know it was an old video. Hope things are still going well!

[@tony359]

No need to be sorry! It was the first successful video of my channel and took me over 1000 subs :) I hope you enjoyed it!

[@liukuohao1]

OMG this dinosaur is alive!

[@tony359]

ahaha yes!!!

[@jameschambers5505]

Thanks for the videos sir.

[@tony359]

You're welcome, thanks for watching!

[@warrax111]

vogons definetly needs more deep hardware section, because there is too much mess in general hardware. I think, they should introduce special cathegory for motherboards, graphic cards, CPU & chipset, etc...

[@tony359]

It could be an idea. Some subforums might help. It also add a lot of fragmentation though. Food for thought. Thanks for watching!

[@uguraltunbilek]

Awasome work and nice video thanks for this beatifuly share

[@tony359]

Thank you for watching and for your kind words!

[@tfhhjh3372]

muy buen canal tengo la misma placa madre me la dono al guien que la estab por tirar ala basura me gustaria que equipo necesito para verificar estado gracias

[@mhajizamanitest]

fantastic quality video . thanks for sharing. Definitely sub! :)

[@tony359]

Thank you!

[@Buciasda33]

try putting back the cache chip. This time it might work. The chips wore overheating because they weren't receiving the right voltage and their input signals might have been in a "undetermined state".

[@tony359]

Thank you, I had the same thought and I did try that - I did not add it to the video to try and keep it of a reasonable length. Unfortunately it still did not work... Thanks for watching!

[@xsc1000]

@@tony359 You can damage chip running it without clock or undefined inputs. So I dont recommend to run system with only 3,3V and missing 5V like you did during test.

[@tony359]

@@xsc1000 that’s very interesting, I suspected that but I wasn’t aware of that. I think I can understand the clock, but what happens with missing supply voltages? Anyways, I’ll keep that in mind for next time thanks!

[@xsc1000]

@@tony359 Missing supply voltages to other part may lead to undefined input voltages of powered part and it can rise the current through both output transistors.

[@baghdadiabdellatif1581]

Great work 👌👏👍

[@tony359]

Thanks a lot 😊

[@devil5051000]

I need a FLIR camera for my repairs. They make work so much easier and are much more precise then the finger method. Unfortunately that babies are not cheap. :( That was a large amount of work to fix something others would have tossed into the garbage bin. Kudos to your efforts. :) Did the halved cache still show up or is the mainboard now L2 cacheless? BTW: Looking at the thumbnail I thought for a second I was in Adrians Digital Basement. ^^

[@tony359]

I hope Adrian won't mind if I took some... inspiration from his thumbnails! The opening is also borrowed from "The Slow Mo Guys" :) The board is currently cacheless unfortunately. I tried fiddling with some 0 Ohm resistors I found on the PCB but that didn't change anything. I'm trying to source some spares but I am not holding my breath! One of my viewers is trying to help, watch this space! I like my thermal camera (Seek compact Pro BTW, took me a while to find a "used" one at a reasonable price) but I have to admit it's not really so necessary for projects with larger components. Definitely more useful when components are half the size of a grain of rice! :) Thanks for watching and for your comment!

[@devil5051000]

@@tony359 If the lower cache (the lower 128KB) chip is missing the higher might not be recognized. So maybe you can at least get 128 KB of cache if you desolder the one still present and resolder it in place of the first one. Had some similar problem with missing chip memory while fixing an Amiga 600 some years ago. Tried to find datasheets with pinout for the installed cache-chips, but found only a thread on vorgons where you were asking about that board shown in the video. ^^

[@tony359]

@@devil5051000 Sounds like a great idea, I will try that for sure. I've felt that chip burning at times too so it might be faulty as well but I guess it won't hurt to try!

[@clementc2e10]

Re FLIR - eBay sometimes has cheap E4 floating around. As most here would know E4 = E8… next level would be cheap E40 which is sort of E60…

[@barnabaskiss2]

First, I would pick up the battery first. Second, I would never use the diode check mode to check connections. The voltage that used by the diode checking mode could harm components.

[@tony359]

That’s a good point which I’ll keep in mind. That said I’m reading that in diode mode you can expect a 2V from the multimeter, worst case scenario 7V at 1mA. A 1996 board should be able to withstand that. But your point is valid of course. Can I ask what you mean with ‘pick up the battery’? Thanks for watching!

[@barnabaskiss2]

You're rigth! I mean I would remove the battery first. I have no idea why I wrote "pick up", sorry.

[@tony359]

@@barnabaskiss2 I agree, that should have been one of the first things to do indeed!

[@JoCrt]

Great video. Many would have given up. 😄

[@tony359]

I can be persistent/stubborn! :) Thanks for watching!

[@tomaszkoszela8433]

Hi i have some issue with my socket 7 motherboard. Accidentally i made some short circuit with my home made VRM module witch i inserted oposide way to the VRM socket. Prewiously my computer worked fine with this modul. Now it report memory feil eaven if i exchange memory modules. Does anyone have some clues what can cause this behaviour.

[@tony359]

Hey, sorry to hear about that. Is that the VRM for the CPU? The RAM is getting power from a different regulator so I guess you might have fried the memory controller which I believe is in the chipset. What do you mean with "memory fail"? Does it POST or does it beep complaining there is no ram?

[@tomaszkoszela8433]

​@@tony359 When the computer boots up, the computer fails the full memory test. After a single RAM recalculation, the message memory test fail appears. I can press F1 and continue or disable the full test in the bios. As it continues it throws a lot of bot errors, tries to recover data and restarts. I am unable to install a new system because critical errors appear right after the start of the win98 installer. computer stops almost all tests in Dos Benchmark pack. When I install only 16 mb of ram then it goes through a full memory test at startup and when I add more RAM, memory test fail appears. bios battery is good

[@tony359]

Sorry for the delay but KZbin seems to keep resetting the option to send me notifications of new replies. Unfortunately it could be many things, I really don't know what to recommend I'm afraid.

[@markg3506]

Very nice job 🙂

[@tony359]

Thanks Mark!