Repair-It

Damn right. Posting this from my old-ass PS/2 Model 70 with upgraded Rev-to-486 chip. It also has a webserver but it seems to ruin the TCP stack when it's running. I am posting this via IE3 and Windows 3.11. For all the performance.

So, who's shocked this worked??

I even did a poll because it's hilarious. I could try attaching something...

Typing this on an IBM Model M keyboard and boy is it loud. Love it. The fact that I just pulled this machine off my shelf in the basement and it fired up is amazing. It has many upgrades such as an XGA card and ethernet card.

Is the webserver running again yet?

Let's see if this works. I tried printscreen, dumped it into Paintbrush and to my amazement it actually pasted the screnshot. Didn't realized that would work but I tried anyway. Here's a 256 color bitmap for your enjoyment.

Damn, I can't upload it. Probably the file picker thing doesn't work. Though I tried typing in the direct path of the BMP and that didn't work either. Boo.

Here

Lol

Fast forward and Ian became interested in this machine so we brought it up again.

It actually booted up and worked perfectly. Then this happened: Needed a CMOS battery. Lithium 223 on Amazon fixed that (no one had one locally, well the Warwick Ace Hardware did but that was too far after already checking like 4 stores in town). I was going to need some floppies so I ordered some on eBay. In the meantime I would also need a computer with a working floppy drive. So I dug out my old upgraded workhorse Dell laptop that ultimately became my Caprice tuning laptop. Even came right up and connected to my wifi because I guess I have kept the same password for a while (and through multiple routers). Battery is trashed but does have something left as it ran without the power connected after charging. First I had to remove the DVD burner and find a compatible floppy drive. Fortunately I did. I became impatient and tried to find some old floppies in my house and I found one which sort of worked but ultimately became unwritable. Had to dig around all of my boxes of stuff for some floppies so I could remake my reference disks for the system and three accessory cards it has. Finally found a few. I formatted them and ran check disk to find the best ones. Quality varied and I sorted them from best to worst. Finally wrote the Model 70 reference disk and it booted into the configuration program. First you have to set the time/date to clear the 161/163 and then it gave me a 165 for config error. This is where I got confused about what ADF files I needed for the cards I have. So I downloaded a handy program that tells you what card is in what slot. Using this I was able to also find TWO Model 70 backup folders buried deep in my archives and had all the ADFs I needed. Originally I was trying to install one card at a time but the better approach is to copy the ADF onto the main reference disk so everything is in one place and next battery replacement, it is all automatic.

Eventually all that was sorted and it once again dutifully booted into WFW3.11. It was all fun and games until I tried installing an Opera browser. During install it couldn't find a Windows DLL. I tried again and same deal. Exited Windows, to this very ominous error: Rebooted and couldn't find an OS on the drive. It would also turn out that the MBR got corrupted and some of the card configuration data is stored there. I figured this out because I made a DOS boot disk. But when the system was POSTing, it didn't count the memory past 6MB. One of the accessory cards is for memory and has 8MB on it so it is supposed to count to 14MB. It didn't throw a 165 but should have....I'll get back to this.

Adam asked about capacitors so I checked. I could see three but they seemed fine? Ran scandisk and it found a TON of corrupted data. In all I think I lost 70MB of data which is nearly half the drive's total capacity. That's a serious event. At this point I figured I MUST be dealing with a failing hard drive. But I kept running scandisk and initially it was finding stuff but eventually cleaned up and was scanning clean. So that was interesting. Decided to run a surface scan where it would flag bad clusters. I assumed it would have a TON. Yes. I watched this thing go and could not believe it. It completed with ZERO bad clusters and no issues. WTF??

I decided to run the system test on the reference disk and, yeah, the hard drive tested sat.

I began to feel more confident but the drive would obviously not boot.

First thing I did was rerun auto setup which fixed the memory card issue. That config is stored on the MBR which got corrupted but there was no 165. Not a normal system state.

Anyway I found my old hard drive backups and thought that if I can just restore critical root directory and DOS directory files, maybe it would boot??

So that's what I did. I had to play games with the attrib command to delete the corrupted files and stuff but some back and forth with my desktop to USB drive to my Dell laptop to floppy and I restored the critical files enough to boot. Rebuilt the autoexec.bat and config.sys to the proper settings to NOT boot Windows and I was back, at least as a DOS machine. I did re-run scandisk a few times to see if writing to the hard drive would cause more issues and it didn't. Then I turned my attention to the hard drive. Why? Because something had to cause this originally. Also, one time it wouldn't POST for Ian until I disconnected the hard drive. So something is up.

Decided to look into the capacitors despite looking OK.

Time to tear down the drive. FWIW, the PS/2 ESDI hard drive module is a hard drive and integrated controller. So the exposed circuit board is the controller. Who knows if there are any bad caps inside the hard drive... Internet told me to push and twist to remove the caps. Yes, really. So I did. Yeah that looks bad actually. And they tested bad, too. Aluminum electrolytic caps. Narrowed down by dimensions and stuff and ended up ordering some Nichicon caps from digikey. I ordered one extra for each type for a total under $10 shipped. Also ordered a TS101 soldering iron and liquid flux. This should be all I need in addition to the solder I already have to get this done.

Bonus info for safe keeping:

Crap, there might be more than 3 on the board...

https://mac84.net/web/repair-guides-doc ... l-wd-336r/

I counted 8 additional ones but maybe they aren't electrolytic...