Hi, I have got original IBM PS/2 board (also with PSU, riser, cards and some cables). It's most probably model 77 - it have i486DX2/66 CPU and onboard S3 928 VGA. I tried to run it, and it displays cmos error 161 mesage and ask to run configuration programs, wait about 10s and then restarts. I read that it doesn't have ROM setup but needs diskette. So I downloaded IBM reference disk for model 76/77 but there is other problem releated to FDD. It also displays message "diskette changle line stuck high". I have original floppy cable and use various 3,5" HD FDDs but all of my 5 drives cause stuck message. But it seems to work, it make short noise when BIOS seek for FDD and light up. So then I tried to pull drive change (pin 34) signal low during post and then message was not displayed but it sill doesn't boot from ref. diskette. I also tried to press various key combinations like ctrl+alt+ins, esc, f1 etc but no success. Any idea? Maybe HW damage of FDC?

I've got a PS/2 model 77. Either F1 or F2 (I was tapping both) produced a setup screen after the memory check. The 720 and 1.44 drives that came with those micro channel machines weren't very reliable so it may be bad. My 77 came with a 2.88 drive. Of course regular 1.44 disks work fine. As I recall those drives didn't have a separate power connection--it was part of the floppy cable. So non-IBM drives may not work anyway. The 161 message may be due to a bad battery

DAVEINCAPS> Tanks, I'll try it. And the setup come from ROM or it should boot the diskette? I don't have original floppy drive, only the cable. It have ~50 pin wide connector at one end and three 34 pin floppy connectors at other end. I need to use separate power cable. Battery seem to be OK, it have 3,08V.

There was no setup disk in it so it must be ROM. Fdisk shows only the dos partition so I don't think it's like the old compaq's with the setup partition on the hard drive. I can't remember how I originally set it up--whether I used a setup disk or keystroke. It's been 7 or 8 years. The 161 may be a date/time error. I didn't check but you can probably find out by googling something like IBM bios error. The model 77 I have is a desktop. IBM also had those towers with 286's, 386's and 486's. I don't remember their model numbers and I have long since gotten rid of any leftovers. (I did keep a few of the 2.88 drives and maybe some 1.44's) It may help if you can find a site showing the pin-out of the IBM floppy drives and see how they match up with regular drives.

Well, I was noticed that PS/2 uses different floppy connector pinout. Wo I'll need to find it and make right cable. I tried to press F1, F2 but no SETUP was run.

I guess you'll have to get the cable/drive figured out first but #1 on this FAQ has the file names for various reference disks. Those links appear to be dead. You should be able to find them here: http://www.ps-2.org/ibm-ps2/refdisks/