The CPU, a 486DX2-50Mhz arrived and I carefully pushed it in the slot. There was not much give, so that was a surprise.
At first power up, I have both power and hard drive LEDs! The CPU also got a little warm, but not hot to the touch. I have to remember these 486 chips below 66Mhz did not require a heat sink. But that is about where the good news ends.

It does not post or have video. This might be the reason it was given to me as little more than a bare motherboard and a partial case. But I am not giving up!

The hard drive could not spin up correctly, so I deactivated it. I actually pulled the cables for all drives, and the soundcard to attempt to isolate the problem. No luck, the most I got was a grayish screen with an out of bounds signal message on my monitor.

Next up I will pull out RAM from another 486 I have and I will try it in this machine. I will also hack a VGA cable to go with onboard video only, in an attempt to get it to do anything.
With no RAM, there is a beep message from the speaker, so that is good. I also got the keyboard Num Lock LED to turn off and on, so those are signs of life.

If this is not the proper forum for this type of log, just let me know. I have not posted in awhile, so my forum etiquette is a bit rusty.

Yep, it was the RAM! I borrowed the entire stash of RAM from another machine. 16MB total now, which is perfect for a pure DOS/ Windows 3.1 machine IMHO.
At power up I was greeted with video! And a whole lot of motherboard errors. I cleared most of these out.

Unfortunately, there were two errors that indicate why this machine was stripped out and abandoned. A 600 series error related to the floppy drive and a general one for motherboard failure.
The "advanced" IBM BIOS is very simple, only two screens worth of information. The onboard floppy/IDE controller appears to be bad, which in my mind explains the two loose IDE controller cards that were along with this PC.
I found only the SIIG controller card showed signs of life. I looked for documentation but found only slightly later cards. I can see the SIIG scanning for IDE drives during boot, but that's it. When plugged in, well, the IBM BIOS seems to hate everything about it.

I tried all manner of primary/slave/cable selects on the primary and secondary IDE connectors on the SIIG. This was between my CD-ROM and my two period correct hard drives. One hard drive was 130MB (smaller capacity than on the stock configuration, I thought a sure-fire hit) and the other was an 850MB. No luck. Right now I will continue to experiment with the smaller drive, configured for 130MB.
I also could not find a way to deactivate the onboard IDE/floppy controller.

I do not want to part it out. Some of these parts might end up in my 166Mhz Pentium 1 build eventually. But considering I seem to not be able to give up just yet...

For anyone that cares, here are the starting specifications from the door:
Model 2155A R57
486DX2-50Mhz
340MB Hard Disk
4MB Memory

And a stamp on the inside of the case
Aug 25 1993

I am kind of out of ideas here, bummer. Real bummer. Any PS/1 IBM experts, please chime in.

Not sure I can help, but I can sympathise.

I recently (about a year ago) purchased an IBM IntelliStation E Pro 6893 knowing it would only successfully achieve post, BIOS. It didn't read the hard drive with the seller. Upon receiving it, like yours have an IDE card installed. Found out the drive was bad. But took going through a huge box of IDE cables before one was accepted.

Thanks for the pep talk, it helps. The direction I am going to go is try to replace all the capacitors on the motherboard. There are not many and it has worked for me before with arcade hardware, not too high of a cost to try out. I remember reading about bad caps in other, earlier PS/1 computers too. This survived so long, escaping being long ago recycled, it is worth a shot. If that does not work I may have to go for a more expensive route, like trying to find a working replacement board for this IBM, IMHO.

And as a complete computer, it can stare back at me now in the corner, looking a lot better for itself than the sorry state it came to me in...several bezel pieces stamped and broken and almost no hardware inside. If computer can have a soul, perhaps it would appreciate being in a better state. It will never be a museum piece or anything, this is all just for fun,. I dunno, but I do feel better about it. 😀

I only wish I could offer more... Opening up the package to find a shattered bezel would have gutted me.

You might have something with the bad caps. One thing popped up when troubleshooting mine was the often mentioned "3 largest caps" that were likely a problem for most. Seen them in mine sitting right beside each other, like Larry, Moe and Curly. They didn't look bad, but I knew this was outside my skill set. Always ran very, very warm (even with the hood off) so it didn't surprise me.