IBM PS/2 55 SX restoration and repair

[@Epictronics1]

Support me on patreon.com/Epictronics Join me on Twitter: twitter.com/epictronics1

[@ultrametric9317]

I did a contract once at United Van Lines. They had a PS/2 that had been printing invoices constantly for nearly 15 years. It had not been turned off in 11 years! Finally it ran out of DOS memory to run DBASE IV which was where the invoice mailing list and mail merge data were stored. My job was to get it going by optimizing DOS memory. It was absolutely filthy inside, end to end. So your dust is likely a sign of extensive use over many years. These computers were very well made.

[@TruckFan542]

I love the way you words things, and the “accent” (or whatever it is). It’s so unique, a bit funny and quite entertaining.

[@BigBadBench]

So many PS/2s! You must have the biggest PS/2 collection around. Great work keeping them running!

[@Epictronics1]

Thanks! I wish I had even more PS/2s! :)

[@onlineworkmail]

He is in a battle with IBMMuseum

[@olivierpericat9224]

I love these PS/2s so much that I can't get enough videos about them ! :) Good job !

[@Epictronics1]

Thanks! You're in luck, there are many more to come

[@GeckonCZ]

Nice work as always, Roman! A note about the RTC module... Most PS/2s perform a rolling bit test on a specific address of the CMOS memory (and the extended 2K/8K NVRAM if the machine is so equipped). If the test fails (bad or missing RTC/CMOS or NVRAM module) you will get nothing on the screen. But you should see a checkpoint code on LPT1 - usually CP 06 for these older machines.

[@Epictronics1]

Thanks Tom! I'll keep that in mind

[@2dfx]

I love these quirky machines. Ahh the frustration of ESDI hard drives.

[@PJBonoVox]

Nice work dude. Was pretty amazed you blamed 4 floppy drives before suspecting the disk though.

[@maxtornogood]

From stinkin' hot pyramids to stinkin' fishy capacitors, welcome back!

[@Epictronics1]

Thanks, I'll probably do fishy caps now for five years before the next adventure ;)

[@AnthonyRBlacker]

Now it brings back all the memories from my youth working on these machines. As I work on proprietary machines like Dell and HP systems and think of the horrible amount of ewaste created by using motherboards that are custom for the silly form factors they use and power cables that don't fit anything else, I recall when I used to build and repair systems as a kid back then any time an IBM system would come in we KNEW we would get $$$$$ for the repair, even though we always just scavenged parts from other broken machines, you couldn't just 'get' parts for these things.. Oh the old days of computers. The best times and the worst!!

[@sa230e]

Yes! I LOVE PS/2s! Can't wait for more PS/2 content.

[@pipschannel1222]

Wow Roman! Looks like new species are arising in that case! I've seen filthy machines but this?! Holy cow!

[@BOBService417]

Awesome video. We are looking forward to seeing a new video of digital microscope soon.

[@itstheweirdguy]

I love watching your videos. Really showcases how the newer stuff we have now has evolved and gotten better. Going from AT power to ATX power was a huge upgrade for PC's! I was born in 1985 so if I get something old like this I might blow it out with compressed air and wipe it down with a towel, but any more than that it goes to recycle. I love how you show us that anything is possible. Of course, when this PS/2 was brand new it would appear normal to take it apart and do stuff with it ;)

[@50shadesofbeige88]

Ayyy he's back!

[@Epictronics1]

:)

[@InitialiseDisk]

Thanks for cheering me up with this video. I found a mouse nest with the mouse in my PowerMac 7100/88 today. Pretty crappy especially since I hate mice! :(

[@Epictronics1]

Oh, that sucks. Rinse it in the shower!

[@InitialiseDisk]

@@Epictronics1 I’ll pluck the pram battery out and stick the whole thing in the shower.

[@Epictronics1]

@@InitialiseDisk That's what I would do :) Dry it in the sun or with a large fan

[@RudysRetroIntel]

Another awesome video! Thanks for sharing

[@Epictronics1]

Thanks Rudy!

[@tankgrrl]

Nice! The ending was, for me, perfect. My mom had one of these... and I played Secret of Monkey Island on it all the time. Insert Disk 22

[@tony359]

How come you always work on PS/2 when I'm also working on a PS/2?? :) I'll re-assemble it today, fingers crossed! Awful design the PSU with rivets!!! Mine has two on the power switch too. I used screws though to put it back. Very nice job and very nice machines! The "bad floppy" struck again :)

[@Epictronics1]

Oh, is your floppy still giving you trouble? It must be cursed! Looking forward to see the final result with you Model 30!

[@UpLateGeek]

Completely filled with nasty dust, you say? The worst machine I ever worked on was at a club during the time when smoking was still allowed inside bars and clubs. It was the machine connected to their poker machines, and used to verify payouts and collect statistics, manage the cash drawer, etc. I don't remember exactly what machine it was, but it was an old (late 90s) small desktop formfactor business type machine, possibly a Compaq, and it had completely died. When I opened the lid, the entire case was full of fine dust and cigarette ash. All the way to the top, you couldn't see anything inside. It smelled so bad, I felt like I was catching cancer just being near it. I just stared at it for a few seconds before closing the lid and going out to the car park to call my boss. Thankfully he agreed that I should _strongly_ recommend they replace the machine, and even more thankfully the manager of the club agreed and I didn't have to try cleaning out and fixing that machine. We always took a spare one with us for cases like this, so all I had to do was swap the machine out and make sure it got onto their network, and we had remote access to restore the remote backup of their database and get them back up and running within a few minutes. As I was leaving, the manager asked what they should do with the machine, if I needed to take it. I told him we definitely don't need it, and he should take the drive out and send the rest to e-waste. What I didn't tell him was the surprise that was inside the machine.

[@JenniferinIllinois]

Congratulations on finding out the secret of the pyramids. 🤣🤣🤣

[@Epictronics1]

😆

[@bikkiikun]

Suggestion for your bucket-list: Climb Mt Fuji

[@Epictronics1]

Mount Fuji is beautiful, I'd love to see it one day from below. But I'm already done with mountains, I've been to Khardung La in Himalaya on a motorcycle!

[@UpLateGeek]

(by the way, the first cable that you referred to as a flat flex is actually a ribbon cable, and the second cable that you referred to as a ribbon cable is actually a flat flex. the term "flat flex" is short for flat flex PCB, which is a PCB that's made from flexible laminated polyamide film and copper traces. the term "ribbon cable" is just a cable that's flat like a ribbon, made from normal wires joined so they're flat.)

[@Epictronics1]

oops :)

[@AlejandroRodolfoMendez]

For reparing plastic you can use super glue plus sodium bicarbonate, but if you need sturdier plastic you can use super glue and policarbonate (the packing foam) it dissolves with the superglue and take the union between the broken plastic as a harder material that bond with the plastic.

[@Epictronics1]

Interesting, what kind of packing foam? thanks

[@AlejandroRodolfoMendez]

@@Epictronics1 the white ones but also works with the plastic from food trays.

[@SockyNoob]

Word of advice: If you see brown or yellow colored dust, it's most definitely nicotine coated from a smoking household. You should wear PPE like gloves because it's absolutely nasty and will spread everywhere if you don't clean properly, not to mention it's terrible for your health.

[@awilliams1701]

I learned a while ago on Adrian's channel that a RTC is required or you get nothing. Also any SMD cap from before 2008 will be bad. Anything after 2010......case by case basis. It would be cool to see if 2010 caps will go 40 years like through hole ones have done, but yeah those early SMD's were trash.

[@TruckFan542]

Wow, this is pretty good content.

[@Epictronics1]

Thanks :)

[@glenncaughey5044]

If Egypt was too hit, I suggest the Canadian Prairies in winter 🥶

[@Epictronics1]

I'v seen it through the window when flying over. I don't understand how anything can survive down there lol

[@friendlywizard6462]

So gutted I thrown our 55sx out many years ago. It had 8 megabytes of RAM and a 60MB HDD, back then just for fun I was able to install Windows 95 on it with a parallel port ZIP drive. It ran quite well even dispite it being a 386.

[@Epictronics1]

I have another IBM 386 with win95. It runs pretty smoothly too!

[@jozsefizsak]

That was interesting.

[@bikkiikun]

You might want to invest in an impressioning tool for those locks.

[@alexatkin]

That's not dusty, I've seen PCs used in bedrooms look worse than that after a couple of years. Not to mention an Xbox 360 in a smokers household.

[@vhfgamer]

How you gonna do it? You're gonna PS/2 it!

[@SudosFTW]

If you ever restore up a 35SX or 40SX, do note there's a newer BIOS that needs to be burned to their EPROMs! the one from September 1991 is the one to have, but if you have the BIOS revision from 1992, it's not backed up anywhere yet and needs to be dumped and sent to the runners of ardent-tool. it's even more desirable but I'm not sure what enhancements the 1992 BIOS ROMs have over the 1991 ones. Probably 486SLC native stuff? SLC upgrades work with the September 91 BIOS just fine but do still need an enabler in DOS.

[@Epictronics1]

I have 35SX to restore, I'll check, thanks!

[@krizator]

Awesome 😊

[@Epictronics1]

Thanks!

[@krizator]

@@Epictronics1 I'm really looking forward to the upgrade video of this 55 model

[@ceilingfanmusic6597]

Thats dusty but its not a terrible amount of dust to fuss about. Maby ive just been exposed to way to many smokers computers tho. Those make this computer look clean in comparison

[@AnthonyRBlacker]

I have a feeling all that nasty dust built up on that system is NOT from 'storage' in a bad location but more from USING it back in the day in a horrifically dusty and damp environment. That doesn't look like storage..

[@SidneyCritic]

We had 45ºC here last week, but 65ºC is nuts - lol -. Rivets that old from the US are probably 1/8"(3.2mm) If the casing is heavy it might be die cast zinc.

[@Tommi-C]

65deg Wow that is hot. I would die in there.

[@Epictronics1]

I think one of the pharaohs did. They left him in the tub ;)

[@Tommi-C]

Aliens😀@@Epictronics1

[@Epictronics1]

@@Tommi-C 😅

[@jerther_]

@@Epictronics1 Could the guide have meant 65 F? ;)

[@Epictronics1]

@@jerther_ That's what I thought. Once inside, I was quickly convinced it was Celsius :o

[@kirusyaga]

That Chip quick or something sounds like Rose's metal or Wood's metal.

[@c_miraa]

Thank you so much for posting this video! I am currently in the process of disassembling my grandfathers PS/2 55 SX, just as dusty as yours on the inside. The harddrive and floppydrive are different revisions however - there is an ALPS chip on the floppy for example. How do I know which SMD capacitors will go bad or should i assume that every SMD cap will go bad eventually?

[@Epictronics1]

That's very cool actually. I wish I had my grandfathers stuff to restore too. Yes, I would recommend replacing all SMD caps in any PS/2 drive because the electrolyte is corrosive. It may take years, but eventually the PCB will get badly damaged. Good luck with the restoration

[@c_miraa]

@@Epictronics1 Thank you for the quick response! I will look into getting the correct caps then. I also got a Commodore PC20-III, but it feels more better to start with the PS/2 with the help of your video.

[@Epictronics1]

@@c_miraa Have you removed the battery in that PC20? I have spend 50+ hours repairing my PC10 after a battery damage. It's still not fixed :o

[@c_miraa]

@@Epictronics1 I have not opened up the PC20 yet - i will visit my parents next weekend and check! Thank you for the warning.

[@c_miraa]

@@Epictronics1 Small update: After an emergency PC-pickup (just couldn't wait until the weekend!), the leaky battery has been removed. First continuity tests after applying alot of IPA look promising - no components seem to have been damaged and it only just started to destroy the closest trace. It seems like I might have gotten away with this one - thanks to you! I am very grateful for your warning.

[@micheller3532]

Great video! Does anyone know what size those two external case screws are? And the nut driver for the clips? I'm helping out a family member and don't have my kit, so I just want to pick up exactly what I need. Thanks!

[@JohnTitor_0]

might as well see the moai on easter island next

[@km-xr5im]

Where are your IBM Thinkpad 240 videos?

[@Epictronics1]

I have removed most of my early videos

[@Brukner841]

my mom threw mine away after storing it for 20 years, yeah....fk, was my first computer, used that model M keyboard til 2018. What was the 386 SX? Model 55?

[@Epictronics1]

That's a bummer. Yes, the 55 had a 386SX

[@jamesdecross1035]

Question: is there a way to install molex power connectors (for a SCSI hard-drive) in these machines? Thanks.

[@Epictronics1]

Yes, absolutely. You would have to open the PSU and solder/add standard PC cables with Molex connectors. It is also possible to get the power from the edge connector or elsewhere on the motherboard, but I think adding proper cables to the PSU is the best method

[@jamesdecross1035]

I have one of these!

[@Epictronics1]

You need to check those caps!

[@Nukle0n]

Ough, that looks like smoker dust, that stuff is so awful.

[@Netbug]

Sure looks like it... I've seen cases with over 6 inches of sticky nicotine-covered dog fur before.

[@SockyNoob]

That was my immediate thought as well. We'd regularly turn down PCs full of that crap at Geek Squad.

[@Epictronics1]

@@SockyNoob I would grab them. These machines need a shower anyways

[@Megatog615]

fascinating i thought ibm skipped the 386

[@MichaelAStanhope]

IBM was actually one of the first companies to use the 386. The PS/2 Model 70 and 80 both had 386dx processors in them in 1987. Cutting edge stuff at the time.

[@Epictronics1]

@@MichaelAStanhope Models 70 and 80 are lined up for restoration. Stay tuned

[@SmoggyLambGG]

❗ No RAM installed!

[@Epictronics1]

Yeah. the board has some memory chips. I mistakenly assumed it was RAM

[@cozmicboy1]

Aaargh just wrecked my ps/2 286..something went to hell with an sketchy floppy converter cable and it burned the 5v rail.. 😢

[@Epictronics1]

That sucks. I'm surprised it fried the power rail. Are you sure? I would imagine the FDD or the controller chip dying if connected to the power rail on the wrong pin.

[@cozmicboy1]

​@@Epictronics1so this is the case, the cable went in to the floppy upside down.. the 5v (3d pin) melted across the cable. Now it gives codes 161,601,1701,163,162 batteri and date was there prior.. also Hardrive light constany yellow.. so either the 5v rail is gone or the two chips for hd and floppy are gone.. probably could be replaced.

[@Epictronics1]

@@cozmicboy1 Hopefully your machine uses generic controller chips that can still be found on ebay. At least the FDD controller is very likely to be a standard part. The rail should be easy to test with a multimeter. Good luck with the repair

[@cozmicboy1]

​@@Epictronics1 yeah I hope so too, had a quick look yesterday and they seem to be in stock but different brands. BTW, you sound Swedish. If so ill drive down with it and you could have a whack at it. great content for your channel