Hey, guys. Having a new issue related to the same 5150 unit. After playing a game for a little while, the video gives up and goes dark. The PSU it still running, but no video. I came back a week later with the intent on diagnosing the issue, and it worked just fine. Of course, hardware issues don't heal themselves and after game playing for about 20 minutes the video shut down again. Remember this unit has the Hercules graphics card. First time, I was playing a CGA game using SIMCGA. The second time, it was a game with native Hercules support.
My guesses are (in order of probability):
- The PSU
- Typical tantalum issues on the mobo.
- Capacitors on the Hercules card (it has electrolytics, not regular tantalums)
Reason I suspect tantalums or PSU is the appearance of other random errors. At one point prior to this, it threw a 1081 201 RAM POST error. But only one time. Next power on, POSTed without the RAM error. Since the video went dark the first time, it has begun reporting 131 error on POST (cassette port voltage according -0degrees).
So I'm thinking something is operating on its hairy edge, and the load associated with gaming eventually overwhelms it. The electrolytic capacitors on the Hercules look fine (no bulging or evidence of leaking), but that doesn't necessarily mean they're good.
Configuration:
- IBM 5150 Series A 16/64k mobo
- 2nd BIOS revision (10/27/82)
- Hercules Graphics card (see pic at beginning of thread)
- IBM 5151 Monochrome CRT
Any thoughts?
“The Bex religious impulse does have its collective side. As in, collect everything and hold on to it whether you remember where it came from or not.”
—Alberto Fossa, Privateer 2
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