IBM 330-P60 repair & GTA in High color mode.

[@AnthonyRBlacker]

Oh JOY! Finding a cracked solder joint is the only major issue is just the best! I had a problem with my Honda - it wouldn't start occasionally and I had NO idea what it was, I thought maybe the key 'security' was a problem but no, there was cracked solder joints on the connector under the steering wheel that lets the key talk to the immobilizer.. I spent 10 minutes reheating and fixing the solder joints and it's been fixed for 5 years now. Free of charge! Yes, that's a GREAT feeling!

[@Epictronics1]

Occasionally it's an easy fix :) This was my third drive that had this issue. Well worth checking on any bad drive!

[@Runco990]

I used to fix coil whine by adding a drop or 2 of crazy glue. Shut them right up. It's a common issue but not a "fault".

[@humidbeing]

Gluing coils down is done as commonly as gluing down capacitors. Totally normal standard procedure.

[@Epictronics1]

looks like that's where we're heading

[@Davide0033]

@@Epictronics1 and i think that a bit of coil noise is also normal i'm not sure, but i had a lot of stuff that made coil noise, some just do that. especially getting older

[@jerther_]

Nice camera work on the extreme close ups! :D

[@Epictronics1]

Thanks :)

[@Ghozer]

Coil whine is not usually a 'fault' it's more of an annoyance, basically when the coil is working at high frequency, it can sometimes vibrate like a mini speaker at a harmonic of said frequency, you can get inductors that are designed not to, or yes, you can glue the Coil (doesn't have to be glued down, just dampen the vibration of the coils) - replacing the coil for a new same value could fix it - but that's only if the replacement is built a little better to not whine... Just glue it :)

[@richards7909]

Thanks for this explanation as I wondered why it whined! :)

[@AnthonyRBlacker]

6:50 if you had a story, as you always do!, and you were desoldering for 2 hours, I'd watch and listen and NOT be bored. You are a very interesting person with some of the absolute BEST humor (as hidden as it may be), your accent is enjoyable to listen to, very soothing to my ears, and you say it like it is. No worries!

[@Epictronics1]

Thank you :)

[@nickwallette6201]

"The pad has come off ... I hope that's not my doing." It happens. I've had a couple PSUs where the pad came off the board, even without electrolyte damage or anything like that. Especially those cheap single-sided phenolic boards, with large components and thermal stresses. This is just part of deal when you maintain old stuff. Some people will say it's a good reason not to re-cap if you don't absolutely have to. I say, if the pad failed that easily, I'm glad to have caught it early enough to fix it, before something _really_ bad happened.

[@felixokeefe]

I remember GTA in 3Dfx mode. That was awesome.

[@Thomsonicus]

@@felixokeefe 800x600!

[@Jackpkmn]

Gluing the coil is an option. The kludge solution is to wedge something soft enough to damp the noise between the coil and something else. Another potential option is to put heat shrink over the coil.

[@Darxide23]

As others have pointed out, coil noise is very often not the result of a fault. It's electromagnetic induced vibration and needs some kind of anti-vibration the same way a fan can cause vibration and needs rubber dampers to stop the noise. Gluing down coils is one way to dampen the noise and probably the easiest for a hobbyist to fix it. You can buy new transformers that have been resin dipped during the manufacturing process as an anti-noise measure. In other words, gluing it down isn't a hack or bodge. It's actually proper maintenance. EDIT: However, it's fair to point out that noise _can_ indicate other problems as you discovered after replacing the caps. "Dirty" power can exacerbate coil noise. Replacing those caps cleaned it up enough to quiet that coil significantly.

[@BigBadBench]

Looking forward to the glue comparison!

[@Epictronics1]

I hope it works!

[@dannyarnold9823]

Coil noise is a feature not a problem. Designing switch mode is a about compromise, gluing components is sometimes a design requirement

[@cbmeeks]

"Arrow keys stopped working!". Ah...the joys of using retro computers. Never ending repairs. LOL

[@Epictronics1]

lol, yeah, always something

[@olivierpericat9224]

If I remember correctly, back in the days when you wanted to play high color or high resolution in DOS games, you had to use an utility called "UniVBE" to activate some SVGA compatibility with most graphics cards...

[@Epictronics1]

I'll try it out, thanks

[@mike_rofone]

​@@Epictronics1 That is exactly what the SciTech display doctor thingy that popped up should be. I wonder why it didn't activate for the onboard card, maybe that one has proper VESA support already? I'd not give up on the onboard card yet. IIRC you can change the video resolution when in game by hitting F11 and then using the arrow keys plus Enter. I'd try that when the screen is black to switch to a different resolution. Maybe that gives an image on the onboard card as well. It'd also be interesting to compare low color mode performance between the onboard and Matrox VGA cards. The matrox seemed to do not too much worse on high color than the onboard one in low color.

[@mike_rofone]

UniVBE also came with tools to specify the refresh rates for VESA resolutions. That should allow you to set the high color video modes to something that your first CRT should be able to handle. I remember using that to make an old PS/2 VGA monitor handle them back in the day.

[@Epictronics1]

@@mike_rofone I'll make a comparison in the final installment

[@Epictronics1]

@@mike_rofone That could be very useful for recording too! My camera syncs to 50, 60, and 80Hz, but nothing in between. Thanks

[@craigrenwick9132]

I would glue the coil to the pcb

[@Epictronics1]

I think that's what we'll do. Let's see what everyone thinks

[@Inject0r]

It is the only solid way (pun intended) to fix the coil whine. It has been done a lot in production too. :)

[@Brianck1971]

Fix it properly. Don't glue the coil to the PCB.

[@Inject0r]

@@Brianck1971hot glue is the factory standard :)

[@Darxide23]

@@Brianck1971 Coil noise is often not the result of any kind of fault. So gluing it down _is_ the proper fix.

[@wimwiddershins]

I sometimes rejuvenate the hot glue by running my hot air over it, to stick down new parts. Especially coils, big caps.

[@Mulletsrokkify]

The noise is caused by the switching frequency being near the top of human hearing range, 15 - 20 kHz. Totally normal to glue it down to damp it 👍

[@vonhapen1]

I remember having a 486SX back then and playing GTA was simply not an option. My brohter had a 486DX-40 and on that machine it somehow works. I got a used Pentium 100 later that year, including an 2MB PCI graphics card with Cirrus Logic chipset. Guess what the first game was I tried out after assembling the new parts? It was just a blast seeing this game running in a playable state. You could even change resolution in this game when playing with high color mode, I think it was with pressing F11(?). Looking forward for the 3dfx-upgrade. Great video. 🙂👍

[@Epictronics1]

Thanks. I'll try out the different resolutions

[@thefamouseccles1827]

I seem to recall back in the day, numerous third-party cpu coolers that had configurations for socket 3, 4, 5, and 7

[@m4rgin4l]

Gluing vibrating components IS the right way to do it.

[@mndx89]

Coil whine it’s more a mechanical problem than an electronic one. It’s caused by the copper wire resonating at a specific frequency and, being no more perfectly attached to the magnetic core due of aging, generates that whining noise. Nothing to be worried about though, it’s annoying but not unsafe.

[@Thomsonicus]

In GTA when in game press F11 and choose a diffrent screen mode. Might work with a diffrent color depth or resolution.

[@Epictronics1]

I'll try that, thanks

[@arlobubble3748]

Never worked on a psu board that cramped! I'd suspect the cramped layout probably leads to premature capacitor failure due to the heat build up.

[@michvod]

That replacement PSU from Magnetek is most likely due to recap also. Those used some crappy capacitors. Some of them leaked badly, where others had really high ESR. I had to repair those a few times, some of them were used in PowerBook Duo Docks and in IBM Aptivas. Also about the coil whine, I had once repaired a PSU that had a nasty coil whine in standby by replacing the ceramic capacitor that was nearby it (I think it was 10nF). The original one was apparently acting as a piezo speaker for that specific frequency

[@Epictronics1]

Yes, I have repaired the Magnatek twice so far:) I'll check the ceramics nearby, thanks

[@Impossiblah]

The reason gluing the coil tamps down on coil whine is because the coil is actually vibrating and the glue is damping the vibrations. Coil whine is not necessarily a real issue but if you find it really annoying that might be worth doing.

[@GenerationAI2024]

Coilwhine, the GTX 400 series had a major problem with coil whine. Should be ok to sound like that they said. Thanks for sharing, great vid :)

[@Epictronics1]

Thanks :)

[@Retro-Iron11]

Fun fact I figured out for the heatsink on a socket 4; a pentium pro heatsink is perfect replacement. You just need to bend in the long end a little. Plus it looks cool as. :)

[@Epictronics1]

I'll try that, thanks

[@Mr_Meowingtons]

it's just coil whine, glueing them down is the right thing to do.

[@Renville80]

I used to service some equipment that had a large (2" / 50mm) inductor on the output board, and if the inductor wasn't anchored to the board with epoxy or RTV, it would make an annoying high-pitched whine.

[@awilliams1701]

modern stuff uses glue on coils because they vibrate. It's normal even with modern electronics.

[@Epictronics1]

So, it should have been glued from the factory? Would you happen to know what type of glue to use?

[@gemedetvideo]

@@Epictronics1 Usually it isn't actually glue that is used to secure coils to PCBs but an acid free silicon compound. You can use common silicon sealer - just make sure what you use is acid free. The regular acid curing variants can corrode and damage components over time.

[@awilliams1701]

@@Epictronics1 no clue. But yeah it's pretty common these days.

[@cabbitkisser2620]

i never played gta on the pc. but i did have it for ps 1

[@bikkiikun]

You said the PSU was a bit sooty. Meaning, there was something getting rather toasty, inside. Two common culprits in my experience are Diodes and Resistors.

[@vhfgamer]

I don't know about gluing the coil, but I do know that wax potting coils is very common. They do it to stop the very problem you seem to be having. I would remove the component and dip it in some liquid paraffin wax.

[@Epictronics1]

Interesting, I did a Google search. It seems to be a very popular thing to do on guitar pickups

[@jerther_]

Very interesting indeed! I guess the liquid paraffin is thin enough it can get into the coil in between windings so it might work even better than glue!

[@turbinegraphics16]

I had that computer, I got it very cheap back in the day at a market and it would crash sometimes, I think about after a year it stopped working so I went back to a 486.

[@Epictronics1]

Was it the PSU by any chance? :)

[@turbinegraphics16]

@@Epictronics1 Probably, I got the system at the computer flea market for something like $30 in 1996 or 97, I just had to add a hdd and I had a computer, I even remember that weird turning on for a second when plugging it in, the seller did admit that it did crash and it was sold as non working but it was fine for win 95 for a while. I think I got angry and threw it out since I was way too inexperienced to fix it. Later I found a 486/100 in the garbage that I took when no one was looking.

[@cbmeeks]

Option C would be to put a Meanwell inside. :-) Otherwise, I say glue it.

[@thomasandrews9355]

Woah there. SXE are low esr and part of the switching circuit. The replacements seem like general purpose, they’ll die pretty quick . I rebuild a lot of psus. I’ve had to recap smps before because someone used general purpose caps and the psu couldn’t bootstrap

[@Epictronics1]

I'll check and see if I made a mistake when ordering. Thanks

[@Epictronics1]

You were right! Two of the caps are of the wrong type. New caps are on the way. Thank you for noticing my mistake :)

[@AndreDeLimburger]

I'd say, glue the coil. Old glue between the windings might have draught up over time making noisy.

[@Putersdcat]

Forget that GTA crap, Try Carmageddon !

[@6LordMortus9]

Holy crap!! I didn't think anyone else on the planet knew about that game! :)

[@2xtreem4u]

Still have it on my old mac

[@lm4278]

@@6LordMortus9 it's on my modern pc now. Still boot it up now and again. Freaking blast.

[@Mr1p0d]

On GTA I if you tap either F10 or F11 you can change the screen resolution, certain cards go to 800x600x16 in hires mode and F8 disables the frame limiter and F6 or F5 pauses the game iirc

[@Epictronics1]

I'll check, thanks

[@SianaGearz]

Just scope the PSU? If it's not too ripply under load, then there's no need to search for a fault, it's fine. Use silicone rated for power supply use to damp the offending magnetic, such as Silastic or Kafuter. There's nothing sketchy about that. Actually use it all over the place, like on that bodge capacitor, because why not. Look, when you look inside a PSU and it looks like a Peter North scene in there, that's for a reason, this is considered a high vibration environment due to all the large magnetics. When you don't gunk it all up, things break off, component legs and pads fatigue. Plus the noise. I think S3 Vision should work! Maybe it just needs UniVBE. Most games came with UniVBE on disk if the game supported VESA/SVGA modes. Try different versions too. My first PCI card was one of those i think and it needed a LIBERAL application of UniVBE all over the place, i wager a conclusion that the VESA BIOS on these was very incomplete. Oh i haven't looked carefully, i'm watching semi asleep on a netbook, so i'm sort of saying this blindly but the buzzing magnetic should be the SB power transformer. I know it's not ATX but given it has soft power, it must be built similar to an ATX PSU, with a secondary controller and whatnot. So that whole circuit doesn't need to work well, it just needs to work. You can also sort of stop looking across most of the PSU since that's all its own circuit, like you should be able to tell what belongs there though idk maybe not all people stare as much at PSUs as i happen to.

[@Uberalles02]

I'll never look at glued on components in the same way again.

[@Epictronics1]

Thanks, I'll give UniVBE a try

[@ruben_balea]

The other two transformers were at least dipped in resin so I guess that one should have received the same treatment as well. That wide yellow tape even seems to form a dam to contain the resin although perhaps they also ran out of thin tape at the same time... I bet it was made at the end of the last shift of the week 😜

[@Epictronics1]

So, it seems :)

[@jerther_]

I wonder if dipping the coil into clear nail polish would do even better? Maybe thinned down a bit so it goes everywhere inside? Would that dissolve the varnish on the coil wire?

[@Epictronics1]

@@jerther_ I better ensure I dip it in something that won't damage it. It is probably impossible to find a replacement coil.

[@AsmodeusDeviluke]

Gluing it will be fine.

[@bikkiikun]

Fun fact, "Marcon" would be pronounced Ma-Ru-Ko-N in Japanese, with Maru meaning round (Japanese love puns).

[@matthewday7565]

What is under the CPU, looks a bit like maybe a MMX voltage interposer - or maybe a 3.3V interposer as the P60/66 were 5V chips

[@Epictronics1]

I don't know what it does. It only has resistors on it. I showed it in detail in part 1

[@OscarSommerbo]

Yes, gluing might feel sketchy, but that is how it is done these days. Since GTA supports Gravis, maybe get a PicoGUS to try out the GUS music. Also PicoGUS can emulate a few different sound cards, IIRC, since you are running low on soundcards :)

[@Epictronics1]

That's what I'm thinking too :)

[@siliconinsect]

Did you test for the FDIV bug? I made it a business buying bad Pentiums off eBay circa 1999. Intel was legally required to replace their defective Pentiums and were running out of Socket 4's so I negotiated for Socket 7 233MMX! Great vid as usual

[@Epictronics1]

Thanks! No, I forgot to check! We'll check in the next video

[@thedopplereffect00]

Could you reduce flickering by reducing the monitor brightness and increasing the exposure time? Not as good as syncing, but it might help.

[@Epictronics1]

Unfortunately, it didn't help

[@GigAHerZ64]

One of the additional vram chips seems to be not fully in its socket. That may be the culprit, too...

[@Epictronics1]

I'll check, thanks

[@nickwallette6201]

You really need to be careful about removing PCBs on floppy drives. Many of them have the optical track 0 sensor on the PCB under the heads. If you so much as loosen the screws on that PCB, you will totally wreck the alignment, and I wish you the best of luck ever getting it back again. Don't ask how I learned this. Twice.

[@Epictronics1]

lol. I have realigned a few drives. It's a hassle but it can be done :)

[@nickwallette6201]

@@Epictronics1 I bow to your superior skills. :-D

[@Epictronics1]

@@nickwallette6201 lol

[@KrissBartlett]

ohh that sucks hahha your good i cant fix that at all very good fix

[@Takeshi.Nakagawa]

Time for some glue!

[@Nukle0n]

Was there a video about this machine before? I don't remember it, what's that thing hanging off the side of the CPU socket?

[@Epictronics1]

Yes, I linked to part 1 at the end of the video. The interposer is a mystery at this point. I showed it in detail in Part 1

[@douro20]

How about trying Display Doctor? Some video chipsets from that era don't fully support VESA graphics modes.

[@Epictronics1]

I'll check, thanks

[@dank1837]

Isn’t a new AT PSU $35 on eBay? How much for all those caps? Is this a proprietary supply?

[@Epictronics1]

This is an early soft power on AT PSU. Well worth preserving in a rare IBM

[@tspawn35]

@@Epictronics1 That makes sense seeing as AT PSUs in general are becoming harder to find nowadays.

[@ScottGrammer]

All electrolytics - even the good ones - fail eventually. God knows I replace them often enough. BTW, did you investigate whether your particular CPU was one of the early ones with the math error?

[@Epictronics1]

I forgot to check. We'll find out in part 3

[@tomekrv942]

I think that now it is easier to buy PC XT than machine with Pentium 60/66 Mhz

[@dolphhandcreme]

Thermal paste isn't that big of a deal, especially for gold metal tops. These CPUs only have some watts of thermal output.

[@nickwallette6201]

Yeah, they pretty regularly never had thermal paste nor pads. Metal-to-metal (or ceramic, as the case may be) conductivity will do the job fine at those power levels.

[@AndrewFremantle]

Regarding the power supply noise, coil noises often change with conditions. I'd suggest getting some kind of variable load and connecting it to one of the rails and fiddling it while the system is on. Does the noise go away if more load is put on one of the rails? edit: I see later you found the noise reacts to physical pressure on the coil. Glue 'em down!

[@SianaGearz]

Furthermore that's likely the SB transformer, there's always the same load on it regardless of what you do since this is not yet an ATX machine. But it must have an independent standby rail to support soft power off.

[@danthompsett2894]

cool machine being a socket 4 are they rare considering the socket 5 and 7 wasnt that far away, weird socket 6 isnt in the Pentium scale its a socket 3 486 socket with 2 extra pin holes. i take it the coil doesnt simply need replacing in which case i would take the advise of gluing it down.

[@Epictronics1]

Unfortunately, the coil is not a common part.

[@TzOk]

You have the footprint on the PCB to mount the "bottom" cap, on a top side...

[@Epictronics1]

I didn't notice! This is hilarious. Why the heck did they mount it on the wrong side?! I'll have to check, maybe there wasn't enough space

[@sebastian19745]

@@Epictronics1 I saw this too, there is space for that capacitor. The thing might be that the traces from the capacitor to the transistor legs are influencing negatively something (the traces add more inductance that at higher frequency must be taken into account) and they opted to mount the capacitor the closest possible to the transistor, soldering it directly on the transistor solder pads. The whine from the coil is just the magnetic core (the black ferrite core) that is not fixed good enough and have space to vibrate. Some hot glue or silicon would do the trick. This may be due to the plastic case of the coil aging and shrinking slightly thus giving room for the magnetic core to vibrate.

[@douggrove4686]

is that memory chip on the motherboard inserted fully?

[@josteinkallevik]

I was thinking the same, it looks like it is not inserted fully into the socket. That might fix the problem :)

[@Epictronics1]

I'll check, thanks

[@WinrichNaujoks]

Am I the only one who can't hear the coil noise?

[@pianoman4Jesus]

eeekkk.... those first vintage of the IBM PC 330/350 with flat face drive slide covers were, in my opinion, bad machines. The next generation of the PC 350 with slightly curved outward sliding drive cover doors were much better. I forget what MHz processors those began with.... Somewhere between 100 MHz and 166 MHz. Also decent (next) was the PC 300 XL which was a Pentium II processor in that same PC 350 model 2 case.

[@tommyovesen]

Great video. But don't bend the legs :-)

[@Epictronics1]

I always unbend the legs! :)

[@retropcs88]

Haha, I have this same one but with a 100MHz DX4, model name is 330-100DX4

[@Epictronics1]

Same PSU too?

[@retropcs88]

@@Epictronics1 No, I don't think it's the same PSU, mine was also broken but it was riveted together and I had to drill the rivets out to disassemble it

[@Epictronics1]

@@retropcs88 Ok, probably the same PSU as in the PS/1 2133 and the similar PS/VP then. They don't seem to suffer from this issue

[@retropcs88]

@@Epictronics1 Actually, now that I'm looking at it, it seems the motherboard Is very similar to the PS/1 2133, but mine has a Cirrus Logic VGA card instead of a Tseng

[@Epictronics1]

@@retropcs88 I've got the Cirrus Logic too. If it's the same board as in my PS/1, you can easily overclock it to 120MHz :) You only need to move one resistor. I made a video about how it's done

[@Txm_Dxr_Bxss]

What is that PCB between the Mainboard and CPU?

[@Epictronics1]

Excellent question. It's a mystery card. It only has a bunch of resistors. I have never seen anything like it. I showed it in detail in "Part 1"

[@Retro-Iron11]

Looks like chipset and cache. Seems to be the only way for the space with the onboard graphics card taking up space.

[@keiiko]

If the glue, duck tape, hammer or WD-40 fix it, then it's a win isn't it? 😁 Try gluing it, if it's electronic fault then it should not fix the problem, right? 🙃

[@Epictronics1]

you're right. That should reveal if there actually is a problem. Now I need to find out what type of glue to use

[@Retro-Iron11]

@@Epictronics1 Hotglue seemed to be the manufacturer choice that I've seen.