First post, by jheronimus
- Rank
- Oldbie
Hi, all
So I'm trying to resurrect this board, but it won't beep or produce any video. The POST card shows codes E0 and 05.
A bit of backstory here: the previous owner tried to test it but plugged the BIOS chip the wrong way and burnt it. When I got the board, I flashed a new chip and tried to turn it on which resulted in the U8 transistor burning as well. I can't remember the original part, but I replaced it with a TIP127 transistor because it's actually silkscreened as one of three options on the board. Another detail is that two of the cache chips on the board were replaced, so there must have been an issue there.
The board does start to beep when I remove the RAM, so I assume it is working, I'm just missing something (hopefully) obvious here.
The board revision is 1.22, I've tried flashing BIOS versions 3.06, 3.05 and 2.05 (supposedly 1.22 should be compatible with 3.06, but still). The chip used is Atmel AT29C010A, the board is setup for 5v flash chips.
I'm using an Ark Logic 1000VL videocard and 2x16MB of FPM RAM that I know to be working.
Here's what I've tried so far:
1) Three different CPUs: Intel DX4 (WT), AMD DX4100 (WT), Cyrix 5x86-100
2) Three different pairs of FPM RAM, both 2x16MB and 2x4MB
3) Replaced all cache chips. It's still 256KB, just 25ns instead of 15ns (didn't have 15ns chips handy)
4) Reflashed BIOS five times, three different versions
Nothing but CPU, RAM, videocard and POST card are plugged in.