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crazybubba64
June 28th, 2017, 06:25 PM
I work in electronics recycling and I rescued a PS/2 Model 80 today.

Plugged it in, flipped the switch, and the mighty beast roared to life with the big ol' 70MB ESDI drive spinning up happily.

But the floppy drive never performed a seek test, nor did the machine output video.

I've poked around at the expansion cards and tried removing all of them and booting, but had no luck. The machine seems to have come with an IBM memory expansion card and an IBM 8514 video adapter. There's also a 3com modem / network card thing. 70MB 5.25" ESDI drive.

The machine has a 20MHz 386 and a 16MHz 387 co-processor.

Power supply seems to work fine, but I can't get it to POST or beep or do anything beyond power on. Any suggestions would be welcome, as I tried looking around and didn't find much in terms of troubleshooting for this particular model.

ardent-blue
June 30th, 2017, 04:43 AM
I work in electronics recycling and I rescued a PS/2 Model 80 today.
I've poked around at the expansion cards and tried removing all of them and booting, but had no luck.
The machine has a 20MHz 386 and a 16MHz 387 co-processor.

Full type-model? Look under the paddle switch for the recessed sticker.

Rushing in where angels fear to tread, it sounds like you did a good thing pulling all adapters. Have you tried pulling the 387?

Next, the CMOS may be corrupt. Or the battery may be flat. The two make a bad combo.

http://ps-2.kev009.com/ohlandl/8580/8580_Common_Devices.html#Clear_POP

http://mypage.intergate.ca/~fspencer/8580prob.htm#BATTERY

crazybubba64
July 5th, 2017, 04:21 PM
Full model is 8580-071.

Battery is flat. Cleared the CMOS

Pulled the 387.

Nothing, just powers on as usual.

It's starting to look like this machine won't be saveable. I know a guy who wants to repurpose the case for a modern machine. Chances are it's gonna get parted out unless there's some magical thing I'm missing :(

ardent-blue
July 7th, 2017, 07:43 AM
I rescued a PS/2 Model 80

8580-071 (boy, that is big iron)

What is/are the memory daughterboards? Should be at least one up by the internal power cabling...
http://ps-2.kev009.com/ohlandl/8580/8580_013.html


http://ps-2.kev009.com/ohlandl/8580/8580_Planar_Memory.html#8580_Planar_Memory_SizesSy stem Board 16MHz (8580-041, 071) 33F8416
1MB 80nS Memory Kit (for 33F8416) 72X6670 or 6450375


If you have two installed, swap them, sometimes there is a memory error at the start of a daughtercard that prevents booting. Usually, if the daughtercard is wrong size or speed, the system will throw a POST error. Since no POST error is shown, my guess is something is preventing boot.

http://www.mcamafia.de/pdf/m80_ssi.pdf
Snippets... Type 1 system board requires a minimum of 1MB functional memory. I think that 1MB can be in connector 1 or connector 2. Here we are.

"Error Recovery

If POST detects a memory error in the first 512KB of memory, the first physical 1 MB block of memory is deactivated. The addresses assigned to the deactivated block are reassigned to the second physical block of system board memory, if installed. If an error also is detected in the first 512KB of the second 1 MB block of system board memory, the system cannot recover. The first 512KB of memory address space cannot be assigned to reside on an adapter installed in the channel.

POST does not deactivate a memory block if an error is detected in the second 512KB of that block. If an error is detected in that area of memory, the 1 MB block containing the error can be deactivated. Have its addresses reassigned by running the memory diagnostics program on the Reference Diskette supplied with the system. Once a block of memory is deactivated, it is ignored by POST. "


Unplug drive power cables.