Let's repair one of the best 486 mainboard - Octek Hippo 15

[@adriansdigitalbasement]

Great work and sweet fix! And yes, why recap something that doesn’t need it? I’m on board with you 100%

[@JorgeCarvalho_web_dev]

Hi! Why recap? because all components have a rated shelf life according the manufacture. May be the 25/30 years old motherboard exceeds that shelf life. Could be working but not in specs. You dont need to change your car oil every 15..000Km, the car wont stop running but you should because manufacturer specs.

[@adriansdigitalbasement]

@@JorgeCarvalho_web_dev all of the components are passed their rated lifespan, not just the caps. With that logic you’d change all the semiconductors and passives. Motor oil becomes contaminants and ineffective, so I would not say that is an apples to apples analogy.

[@warrax111]

@@adriansdigitalbasement exactly. Also, in car, you have all your life, and life of passangers. That is not good example, to compare it to board, where you have almost nothing to lose. Particulary on old hardware, where you will for sure not running some sensitive database, or something important, but mostly you use it only for play.

[@JorgeCarvalho_web_dev]

@@adriansdigitalbasement Nop, I will not change all semiconductors. A 150 ohms resistor will be always 150 ohms and we can consider it of one type of semiconductor, it retains its specs until it burns out by external factors. A capacitor due to the way it is produced will change its own original specs over the time.

[@JorgeCarvalho_web_dev]

@@warrax111 It is a good example to compare oil changes to change capacitors. You are not forced to do it, the car will continue to start, like capacitors, you are not forced to change it. Some day the board wont boot (the car will start but will damage the motor) analogy. But I understand that you support Mr Adrian thoughts because he is considered a "star" on the YT world, and what he says is the law. I can not support he's argument or thoughts about the capacitors, so if and when I can, I present my own arguments

[@SimmanGodz]

A new Necroware video on Christmas? What a gift! :D

[@MrFixiit]

nice repair i spotted that burned out resistor right away and was shouting at the screen lol

[@robertbezak7605]

I absolutely love these types of resurrection movies. Thank you.

[@tuxer88]

I really love your repair videos! As a kid i was experimenting with 286/386/486 and Pentium I mainboards. Before companies cared about their data getting leaked, i was able to collect huge stocks of old PC's from several enterprises. I once recieved 35 Compaq Prolinea's 486. Seeing them now on Ebay for sale for several hundreds of dolars, makes me sad that i once decided to throw them all out. I also repaired pc's for costumers and sold machines on, what was back than, the very beginning of the internet (1997 - 2005 ish). Seeing this brings up so many memories, wherefor i'd like to thank you! Greetings from Belgium

[@necro_ware]

Don't be too sad, we can't carry everything anyway, but the best of it is always with us - the memories ;) Have a nice holidays.

[@thedopplereffect00]

I'm glad you did not burn your thumb holding that transistor down while soldering at 400°!

[@MarcoGPUtuber]

Twas the night before Christmas, and all through the house, a Zombie hand was twitching to repair a motherboard.

[@RetroMechanic]

Merry christmas! I see that resistor first time, when you zoom to regulater I think that you miss that. but you find it!

[@johncoops6897]

Not only did he miss the burnt resistor, but then he incorrectly named it as a "fuse" and moronically he even replaced it with a fuse. WTF?

[@angelgrig72]

Perfect Christmas present for us!

[@Num1shark]

Merry Christmas from Cincinnati Ohio! 🎅

[@ryant2568]

The good-old 486. My first ever computer.

[@wskinnyodden]

That DX50 was technically the first CPU that forced active cooling to be required and it was also the reason that VLB started walking towards its demise as VLB cards would have to run at the same speed as the CPU FSB a LOT of VLB cards started dying when used with DX50 CPUs due to the 50Mhz FSB. That said, first generation PCI cards (when using similar/equivalent chipset) would be slower than the VLB counterparts when running on a 50Mhz FSB system due to the PCI BUS being clocked at 33Mhz and having additional layers between the cards and CPU. Please note that the same will not remain true when you move up in CPU generations, this will be valid for 486 systems with VLB and PCI slots. I would actually love to see you test a board that has both VLB and PCI slots with a DX50 CPU and VGA cards with the same chipset but in VLB/PCI versions. Another good test will be VLB HDD controllers with RAM for CACHE, as the PROMISE ones that used a 286 as a dedicated HDD controller, though in this case the problem is that I never found a version of those cards in a PCI version, though the VLB really kicked butt *once their drivers where installed that is*, specially in Novell Netware 3.x file servers when you have a bunch of users hitting the same databases at the same time, those things rocked hard with 8Mb of RAM dedicated to HDD cache. They also considerably sped up Windows 95 on 486 systems (or even Pentiums with VLB slots). It took years before a normal PCI controller and HDD matched that performance (When comparing IDE devices, SCSI devices are not in these considerations).

[@sammyjunior4168]

You are right the DX50 was a boy ready to run in the 32 bit era. It was mind-blowing

[@cynic3859]

Что касается частот на VLB -- в одной из моих сборок система стабильно работала на частоте 66 MHz. (Процессор 486DX2-66 работал как "DX2-133". ;) ) С шиной PCI также было не всё просто: в период становления стандарта PCI v. 2.0 встречались MB и видеокарты, способные работать на 66 MHz. Процессоров, работавших на такой частоте мне не встречалось, но попадались экземпляры DX4-133, работавшие как "DX3-180". Правда, переключение частоты с 33 или 40 на 60 приходилось делать уже после старта системы.

[@wishusknight3009]

Most PCI implementations would run 1/2 at 25mhz on a 50mhz fsb. I have a UMC 486 board that has both pci and VLB. And it will drop the PCI to 20mhz when I put the FSB to 40mhz. Which is a shame. But its VLB implementation also seems to be very slightly lower performing than a pure VLB board I have when replicating configuration as closely as possible. I have found on my VIP board that when the busses are the same speed then the VLB is only very slightly faster using my friends ET4000 cards. The difference seems a little more pronounced on a dx4 than on a dx2 as well. But they are still both within a few percent. And best comparisons I can make with HDD controller's indicates they are identical for the most part. Both using flash and spinning rust. However my VLB board seems to outperform the VIP board I have by a more significant amount.. So I can't call that apples to apples as its probably got other optimising going on. We even did comparisons with L2 an L1 disabled at different stages to see if we could isolate more situations. And the differences seemed consistent.

[@cynic3859]

@@wishusknight3009 В период становления стандарта PCI 2.0 встречались m/b и видеокарты, у которых была документирована работа на 66 MHz. А некоторые бренды и ранее выпускали компьютеры с "заводским разгоном". В таких случаях комплектующие сторонних производитетелй были не всегда совместимы (если не могли работать в разгоне). (Позже - поддержка 66 MHz осталась только на "серверных" PCI-64.)

[@wishusknight3009]

@@cynic3859 There are many cards that had 66mhz capability. Even though they were 32 bit PCI. Silicon Image SATA cards for example are 32bit - 66mhz. And several video cards were capable as well. Including the VOODOO 3 and ARC Logic 1000PV PCI vga chip

[@FOIL_FRESH]

can't wait for the benchmarks. love your repairs!

[@wishusknight3009]

I am brimming with anticipation. I think I already know the outcome, but I always like how Necro tries a few different and oddball configurations.

[@modlabs]

Thanks a lot for this repair. One more time - noce job. Waiting for nex videos.

[@PavelUrusov]

Excellent video, as usual! This is definitely a great 486 motherboard.

[@wishusknight3009]

Probably one of the arguably few that was better was the infamous PCChips board with the fake cache. It really sucks they had to tarnish that board that way. Because the implementations on that board are otherwise simply fantastic. With a bios that can be tuned exceptionally well and supports all the cyrix 586 features with a simple toggle. And with its legendary and hard to find cache chip, it is among the best performing boards for socket 3 ever made.

[@alpine7840]

Merry Christmas

[@necro_ware]

Thank you! And wish you a Merry Christmas as well!

[@up2tech]

Merry Xmas NecroWare!

[@necro_ware]

Thank you! Wish you a Merry Christmas too!

[@bASICMiner]

a 486 DX2-66 was my first PC when I was in High School... I got it in my third year... pretty awesome!

[@alexv3780]

The burned resistor R11 looks like a current sense resistor, the R14 above the small transistors is probably used for Vout feedback. The resistor (R11) is probably 0.5W or 1W but it is not a problem as it'll disipate 0.04W at 2A.

[@johncoops6897]

Agreed. THAT IS NOT A FUSE! I have no idea why he keeps saying "the fuse", when there is absolutely no indication, PCB marking (R11) or component marking to make him think that. I also cannot work out where he gets the "5 Watts" from (once again, there is no reason to think that). And why on earth did he replace a 0.01 Ohm resistor with a 3A fuse? WTF??

[@felixokeefe]

@@johncoops6897 There is such a thing as a fusible resistor. I'm fairly familiar with this type of circuit and I'm fairly confident that it doesn't make use of a current sense resistor. If it did it would need to be a precision resistor not a 10% tolerance wire wound resistor.

[@VShuricK]

@@felixokeefe for digital electronics of that era 10% tolerance fully acceptable.

[@monad_tcp]

@@johncoops6897 Because a fuse is a 0.01 ohm resistor

[@monad_tcp]

@@johncoops6897 even a straight wire is technically a fusable resistor, (it will burn like a fuse if you try something like 10A at 5V)

[@artursmihelsons415]

Another one great repair and another mainboard is rescued from chip heaven.. 👍 I enjoyed, as always!

[@TekJones83AJ]

Awesome vid and very informative. Thank You and Merry Xmas! Can't wait for the Comparsions.

[@cybercat1531]

Nice fix I've had almost the same failure on a SiS496 based board with a multi voltage circuit of this type. TIP127A failed in a low resistance mode from Gate to Source and was providing very low voltage output. Swapped it for a BDT64C and all was happy again.

[@ms-dosman7722]

Once again, nice job at repairing this system! Looking forward to those cpu benchmarks!

[@tomp538]

Nice video. The Cyrix cpu brought back memories of my first attempt (successful) pc upgrade, back in 1995.

[@WXSTANG]

I remember way back in the day I had a DX2 66 that I set the mainboard jumpers to 100mHz. Ran that thing for years without understanding I overclocked it, I just knew it was running better. haha It wasn't until I upgraded to a Celeron 300a that the overclocking community became wild and I finally understood what I was doing. In any case. Cool video!

[@sidrt4648]

Excellent video again 👌

[@deepmaze1]

You've inspired me again!! I took problematic LS-486E Rev C board and put into my 5x86 build. Then I did a CMOS reset to defaults and from the very first try it run on 160Mhz. Without any issues. IDE issues had disappeared magically.....I've spent a year trying to start that board with internal IDE controller.

[@user-et1vj1oz3f]

Good repair!!!! 20yrs old rubycon cap at me has low capacitance and i replaced, before recap test the cap! Every time! Merry Christmas!

[@askoldmodera]

Наконец-то ютуб порекомендовал мне канал с ремонтом старого железа, давно такой хотел.

[@RixtronixLAB]

Vote it up, nice video clip, thank you for sharing it :)

[@LadislavHuttl]

OMG! I just love your videos, I'd really have the knowledge of yours to identify the issue on the board and fix it. Thank you very much!

[@Carcenomy]

That was a really eye opening video... I feel like my Christmas break might be trying to resurrect the old AOpen AP43 I've got lying around now :)

[@necro_ware]

I certainly wish you a lot of fun and a successful repair ;)

[@wishusknight3009]

SiS VIP! oooh, great board. Well worth the effort.

[@daw7563]

I totally agree with you about recapping. If it aint broken don't fix it. There is no such thing as "future proofing". However computers with known cap issues should of course be recapped (like some newer Amigas and Macs).

[@dragoncracker]

excited to see the show down and impressed to see you bring this board back to the land of the living

[@wittonleung8732]

Great XMAS gift for retro guys, greeting from my comatose Octek Hippo 15 mobo ^&^

[@minombredepila1580]

Excellent repairing example. Learned a lot from it. Thanks for that 🙂

[@Maciej.R.]

As always, a good deal of information. It was nice to watch. I'm waiting for the next one.

[@foobar-9k]

Great video, and great to see that "old lady" brought back to life :-) Greetings from Argentina!

[@FanaxLt]

You're the Gendalf of old computers :)

[@catcam]

Merry Christmas from Croatia!

[@necro_ware]

Merry Christmas to you too!

[@eerchant]

Great video! thank you!

[@pentiummmx2294]

nice job at getting that old board working again, and it has a award bios.

[@redavatar]

I own 5 IBM PCs (PS/1 Value, 386 PS/1, Aptiva 486 SX, PC 330 and Aptiva P166) and what always struck me is how none of those PCs have had any failing parts (yet). I've had people telling me I should recap all those boards but something tells me that the better brands didn't buy garbage components to cut corners. I had to get my Amiga 1200 recapped for example (shows how Commodore was cheaping) but my IBM PCs are built like tanks. Even their CD drives still work perfectly. Mitsumi made some rock solid drives back then.

[@fancyfakename8967]

Yeah it was around S478 and 775 that the counterfeit cap solution from china infested the market, the stuff before that was built like a tank.

[@qzorn4440]

it is refreshing to see the little O-scope being used for the hobby budget people... 🥳 whereas, using high dollar equipment for the same results. 🧐 thanks a lot. 🐥🌴🥂🍻

[@TC_here]

Looking forward to seeing the bench marking test..

[@GodmanchesterGoblin]

I was literally shouting at the TV watching this until you got to that fuse / resistor. It was so obviously discoloured to my eyes. When I was working I always encouraged younger engineers to power off and take a long hard look at a board for damage / manufacturing defects / damaged components before resorting to electronic debugging. And I agree 100% on not replacing capacitors without good reason - you can do more harm than good if not careful.

[@necro_ware]

Yes :D I always take a careful look actually, but sometimes I seem to be blind. As I finally saw that thing, I was laughing and sure, that everybody else would've seen it from the beginning.... But I think, this way it was more entertaining for everybody and this is all about that eventually :)

[@osgrov]

Ah yeah, a 486 video for Christmas! My favorite PC-platform, the 486 was (and is) so much fun. Looks like a really nice board, haven't seen that one before. Looking forwards to the upcoming benchmark video! :)

[@FeArhsma21]

I was 890 Likes. Merry Christmas And God Bless!

[@esc2dos]

This was great, really enjoy the way you explain your process it's so helpful. I managed to find a green UMC CPU myself, can't wait to see your results.

[@Ketma73]

Awesome, you sir, are a master at repairs. Merry Christmas !

[@crtified1001]

Thank you for another informative and interesting video. It would be great to one day perhaps see a video where you discuss which measuring and testing equipment you use, for help others get started in similar hobby.

[@PatricksRetro]

Thanks a lot for this great video! I learned so much from your channel already. And this one gave me some ideas what else I can check on my Hippo board that currently does not work as well 🙂 +1 also on the recap mentality. I also only replace faulty ones and that worked very well so far.

[@osamely_varan]

great job.

[@MattBaker1965]

Nice to see a AMD DX 40 MHz at the end of the video... My first NEW PC had that CPU in a VERSA (VLB) extended MoBo. All the I/O wend through a VERSA multi I/O card. It was the same price as the Intel 33DX offering so I went for the speed. Of course the box shifter shop I bought the PC from when bust while I was waiting for the PC to be delivered.. But another comany in the same shop with a very similar name delivered the PC. That was how it was in the 90s kids ! :)

[@SergiuszRoszczyk]

I'd like to say thank you. You're doing great job here. And I decided to revive my P4P800 board. It worked 2 years ago but... Now it doesn't (posts the dies). I have two of them. Both with similar result. After messing around I know that I have to replace all VRM caps (70 deg C after 10 minutes is not normal...) 😁

[@necro_ware]

Yes sometimes it needs to be done. Especially on the P4 and Athlon the caps were under very heavy load and tend to go bad a lot faster there.

[@SergiuszRoszczyk]

@@necro_ware I hope it is. Board worked for half an hour and then died on my eyes. Second one randomly forgets settings, crashes on memory count or reports BIOS checksum invalid and starts in BIOS recovery mode. On the first one I thought it was CR2032 or RTC crystal (your video about interrupts inspired me for this investigation), but scope said "it is OK" and fresh battery didn't help either. PDF from ICH5R says everything including CMOS RAM is integrated so I hope it is about bad caps 🙌. Also funny thing that Watchdog randomly shuts down power to that first board. I replaced any other component PSU, CPU, RAM, GPU... Nothing else left ;)

[@knyshov]

Always a pleasure to watch one of your videos. I learned a lot of CPR techniques from you. :)

[@smtkr]

I can't wait to see you benchmark and overclock on this thing.

[@orinokonx01]

I have this board and set it up with 64MB RAM, S3 Diamond Stealth 3D 2000, VooDoo 2, SB AWE32 running Windows 98SE and it performed beautifully! Even managed to run Half-Life 1 on it, if a bit slowly (but the fact it ran at all using the VooDoo 2 was amazing!) Great video and certainly something I'll be watching out for on my board!

[@necro_ware]

Hehe, even Voodoo 1 is an overkill for a 486. The FPU is simply too weak to feed the GPU. I bet, if yoy replace the V2 through V1 you will not notice any performance difference.

[@orinokonx01]

@@necro_ware oh I know! But sometimes it's not about what makes sense but rather the absurdity of it all! I remember being a kid and getting win95 booting on a 386, and even though it took half an hour to boot, it managed to do it. That was the fun of it all. The challenge. Right now I've got a dual PIII system set up with an Nvidia FX5200 and 768MB RAM, running WinXP, just to play a nosteam copy of HL2. Why? Because! 🤣 It's just for the fun of it.

[@necro_ware]

@@orinokonx01 Hehe :) That's true

[@madATcomputer]

My first PC had an Intel dx50. Brings back a lot of memories. Cool main board glad you were able to repair it.

[@wishusknight3009]

I had an EISA server with a DX50 for a while many years ago. It was quite a neat machine and seemed to have some pretty good performance. It seemed comparable to a dx2/66 in some things.

[@donglekludge9219]

Subscribers gone up about 1000 in the last few days?! Hopefully that continues. It's about time your channel got some more recognition. I think I've binge watched everything in the last couple of weeks. Grüß aus Sachsen.

[@necro_ware]

Moin zurück! Ja das ganze scheint jetzt etwas mehr Beachtung zu bekommen, als sonst.

[@SakiSkai]

I love your repair videos, you should do more of them

[@joaoc_PT]

I love this stuff, thanks!

[@Hessi]

Deine Videos sind Entspannung pur. Benötige ich gerade ganz doll.

[@Hessi]

Das waren damals schon geile und spannende Zeiten. Was habe ich da noch herumgebastelt und ausgetauscht. Heute habe ich einen i5 4670K mit 16 GB seit sieben Jahren. Klar, immer mal wieder SSDs hinzugefügt - letztens sogar eine NVMC in einem PCI-E-Slot (weil ich doch gerne bastele). Aber das Ding reicht mir immer noch für alles (inkl. Videoschnitt). Einzig 360 Grad-Bilder und -Videos lasse ich auf dem Handy rendern, weil die RX570, die CPU und alle Lüfter auf Anschlag gehen und es trotzdem länger als auf meinem bald drei Jahre alten Redmi Note 5 dauert (das dabei nicht einmal handwarm wird). Wenn es nicht bald ARM-CPU-Mainboards gibt, wird der Nachfolger meines i5 ein M1. In diesen sieben Jahren hatte ich damals: 384/40, 468 DX2/66 (@80), An5x86-133, AMD K6-166 (@200 (2x 100 MHz)), AMD K6-2 400 (@500), Athlon 1.300, Athlon XP 1600+ (@1,66 GHz). Wahnsinn, wie viel Leistung zwischen dem 386/40 und dem XP liegen. Mir juckt es nicht in der Hose, wenn ich an einen Mittelklasse Ryzen denke. Schöne CPUs, aber uninteressant für mich. Was ich als PC-Spiele in diesen sieben Jahren (und danach) an Geld für Grafikkarten ausgegeben habe, passt auf keine Kuhhaut. Das waren viel mehr Grafikkarten als Prozessoren. Nach dem XP wechselte ich 2004 von Windows zu OSX (Powerbook 17" G4 1,33), dann zu einem C2D 4300 (@2200 MHz) (Hackintosh) und dann eben erst zum i5 4670K, den ich bisher nur zum Spaß übertaktete, aber sonst im Default laufen lasse. Vom Hackintosh bin ich jetzt ein Jahr weg. Ubuntu bietet alles, was ich benötige. Nur für FinalCut starte ich noch den Hackitosh, ganze selten mal Windows für alte Spiele. Ich zocke nur noch auf einer alten Xbox 360, die Switch benutze ich gar nicht. Sorry für das längliche Posting. Liegt wohl am Jahresende, dass man mehr über die Vergangenheit nachdenkt.

[@ayan.debnath]

You are AWESOME!

[@RetroSpector78]

Great repair dude ! Really enjoyable to watch. Like the pacing, clear explanation and background info.

[@jameshare1848]

Brilliant video - Brilliant channel. I could watch your content all day. I really miss my DX4-100

[@rakeshpk9648]

nice job.

[@rs-qq3os]

I love your videos and as always waiting for more :)

[@thesmokingcap]

Man that's cool! Saved from the landfill! It's nice having a 486 with PCI as it opens up great options for expansion cards

[@lorenzo.c]

Soldering on such large copper planes/areas really is a pain! A large chisel or hoof shaped tip should help. In the video I could not see it if you did it but wetting the tab of the MOSFET with flux paste before laying it down on the melt solder should have made the process just a tiny bit easier.

[@necro_ware]

Yeah, I probably threw it out during editting. Some flux is always a good idea.

[@theSoundCarddatabase]

Thank you for this video! Very enjoyable, and a great success! For the "mandatory" recapping : I apply the "if it's not broken don't fix it" mantra :)

[@SianaGearz]

I'm not a proponent of "recap everything" either, it's good to recap based on findings and experience. These are nice caps. If there has been little to no degradation in 25-30 years, it'll be fine for another few decades, which is not a guarantee when you install fresh ones. Run under benign conditions and manufactured without as much spec and footprint pressure with known good chemicals, old caps can be remarkably long lasting.

[@jcams438]

Nice video! Im so glad I found your channel. 😀Its very nostalgic.

[@TheCarlos206]

Flawless!!!

[@Vermilicious]

Nice fix!

[@DavoShed]

I was so proud of my 486 DX2 computer when I first got it new. I seem to remember paying over $3000 for it. I used it for many many years. Maybe it’s still down the back of my shed ;) Great video. I have leant a few diagnostic tricks. As for replacing all the capacitors. Not sure why you would want to do that. If it’s not broken don’t fix it I reckon. :)

[@stamasd8500]

Very cool. Around 1996 I was still using a 486DX2-66, built around the (in)famous Octek Hippo DCA2 motherboard. Unfortunately I was stupid and once I upgraded to a Pentium II a couple of years later I got rid of that motherboard. I'm still sad at my stupidity.

[@sandmanxo]

I'm not sure if this was a US only thing, but EDO ram was pronounced by it's individual letters and not as ed-oh when it came out. In any case excellent video and I wish I had your troubleshooting skills. I've tossed many an old board in the trash if a recap didn't fix the issue. I'm also a big fan of early 80s arcades and a recap is the first thing I do with 40+ year old caps. After a string of terrible caps in the late 90s/early 2000s super socket 7 and p3 boards that didn't even survive more than 3 years it's typically my only troubleshooting step, but I haven't messed with those boards in over 10 years at this point. I think at this point I only have one socket 3 board left and have a Cyrix DX2/80 in it. I'd like to get my AMD 5x86/133 back up and going at 150 again like I had during the 1996-1998 era with my Diamond Stealth 32 VESA vga card as that was the only 486 I ever had that rivaled early lower clocked p54 pentiums of the time. I'm hoping to get some time soon to try this out as my old socket 7 and socket 3 systems have sat around for over a decade without trying them now. I even have a Gravis Ultrasound in my K6-2 533 system and want to get in going again as it seems to be a very rare find these days.

[@Ojref1]

Absolutely correct on the capacitors. As long as they aren't visibly leaking or you can ID them as fake, and the ESR is good, no worries. If they're cheap no-name/chinese made units, or your board is known to have the fakes, then by all means. I recently rehabilitated an old Neo-Geo MVS arcade board, and I had to redo the electrolytics because time and heat had visually taken their toll.

[@surjo55]

Became nostalgic, my first pc was built with oktek rhino main board that just came with pentium mmx processor support. It is still with me but didn't power on for a long time.

[@DxDeksor]

Nice repair ! I actually own the same board and it's not working yet. When I first got it, it was covered by mud and most of the board's metal looks a bit dull. I guess years of moisture got rid of the shinyness of the board. Of course I cleaned it before trying it. Last time I tried it, I remember once in a blue moon having a post code, so there's some life left in it. I remember trying contact cleaner Today I powered it and to my surprise I got a post code every time ! However when I put ram it always gets stuck at code C5. Moreover the jumpers were a bit wrong so I changed them. Then I got no post code ... It seems that the clock generator set to 33mhz prevents the board from outputting post codes. Setting 25mhz worked like before. Then I checked the CPU voltage and to my surprise I saw 4.5/4.0V Since I saw your video I checked the regulator's resistance and I got like 20ohms. So just like you this doesn't look right. Now maybe I'm a bit paranoid, but maybe this transistor just doesn't age well ? Also there was a burned trace behind the CPU socket. I don't know what it was made for but it didn't prevent the board from outputting post codes and fixing it didn't solve the issue I had (but of course that trace was probably doing something important). The fuse on mine isn't blown and isn't dark. Or maybe both our boards got the same mishandling resulting of killing the regulator ? So I guess my next step is to swap that regulator just like you :)

[@necro_ware]

Such power transistors in the linear voltage regulator circuits can get really hot and on this board there is not much of a heat sink except of the copper plane underneath. Due to the stress those transistors are notorious to give up one day. In my opinion this is the issue number two on the 486 mainboards right after the barrel battery. The burned trace behind of the CPU is may be a sign of a wrong CPU insertion, I hope, that is not too complicated to fix with a jumper wire. With only 20 Ohms you certainly should also check out that transistor indeed.

[@jameshearne891]

As others have said, R11 isn't a fuse, it's the current sense resistor that lets the cpu power supply section monitor the cpu current and probably shut it down if the cpu draws too much current. By replacing the sense resistor with a 0 ohm fuse you have effectively disabled the current limit circuitry. The cause of the fault was probably a failure of the FET going short which took out the sense resistor.

[@necro_ware]

Yes meanwhile I also think, that it is a current sense resistor indeed. However, since I replaced it with a 3A fuse it would limit the current in a hard way :D I guess, I will have to search for a proper replacement...

[@DevilbyMoonlight]

I always remember my 1st '486 mainboard, the PT-429 by Pine Technologies, I ended up fitting hundreds of these in builds, even though they were VESA and the early ones didnt have a Zif socket

[@BrassicGamer]

A very satisfying repair!

[@DanielLopez-up6os]

Wonderful Fix man!

[@AshenTechDotCom]

i wouldnt re-cap unless caps look like they are going OR questionable quality... OR rarely i have helped racap boards that came with undersize caps allowing better chips to work stable under extended loads... (few biostar models are like that) this video just gave me memories of doing repairs like this when these boards were still in regular active use... also, alot of Micron Pentium boards dont do EDO either, yet a few of their 486 boards we delt with liked EDO better then FP(a couple ONLY would use 72pin EDO or 30pin ram..... but not fp ram... weird as that may be...) i dont miss those days... outside how easy most stuff was to repair...

[@vooduofduty]

Great work!! Excellent vídeo!!

[@sarbenminari2013]

Нравится, что помимо интересного процесса ты все доступно комментируешь, занимательные видосы получаются.

[@andressepter]

Really cool repairs and informative channel. Tho I wonder what one does with all those repaired motherboards.

[@Jorge_Ramirez]

I really think it was the transistor that went bad first causing the fuse to blowup.

[@Johnnii360]

Recapping on such old hardware is recommended because the electrolyte is getting dry over time - especially in this long time. It can work but it's like Russian Roulette.

[@mstrVLT]

you are wizard!

[@glitchwrks]

Nice fix! I bet someone put the CPU in backwards, I had several that were given to me in the late 90s/early 2000s when 486s were merely obsolete that suffered the same death. Agree on quality capacitors like Rubycons not needing replaced, as long as it's not from one of the cap plague/counterfeit eras. I often end up recapping boards that we use in test systems or customer machinery anyway, since the cost of downtime far exceeds the time and effort to recap...but that's a little different :P

[@BorgSwarm]

Great repair and video. Where did you get that component tester you use? Is that something you built?

[@necro_ware]

No, I bought it on AliExpress years ago, but I made some modifications to it.

[@googleevil]

спасибо за детектив :) Очень интересно.

[@aublak7492]

Sick board. Any socket 3 board with PCI is a valued item.

[@gordoncreAtive]

Metal memory clips!

[@funkykoval2099]

Good, another one cpu brought to work again!!! I wish i had your skills and could repair my geeforce mx400 on pci. I had psu surge and card got overvoltage. I know it's only gfmx400 but finding it in pci took me almost 2 years.. Have You tried hardware DVD decoders on 486? Merry Christmas!!!

[@naib_stilgar]

Great save!

[@badrolix]

Молодец, отличная работа!