Nice work ! Glad you found it. Possible it worked ok at factory but had very thin via plating which with time just failed (have had to open+solder via's that were not proper a few times).
Hate posting a reply and then have to edit it because it made no sense 😁 First computer was an IBM 3270 workstation with CGA monitor. Stuff: https://archive.org/details/@horun
@Horun
Excellent point! The vias on this board are exceptionally thin-walled and really do not seem to be that well plated.
Opening it up and actually repairing it in that regard might be worth it long-term. The bodge I have going was very hard to solder, but it works...mostly. There's an update below regarding the ARK1000VL.
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One minor update that might indicate there's more work to do:
It appears that the board is only partially stable with an ARK1000VL (Paradise Bali32) in the secondary VLB slot. The Trio64 works fine, but with the Bali32 in the slot, it appears that the board will hang in, say, SpeedSys. SpeedSys runs just fine on the board with the ARK1000VL in the first slot.
After the board hangs, I find that I have to fiddle with the 0/1 ws jumper and the <=33MHz jumper to get things going again, otherwise the POST card entirely skips to POST code 31 and the board complains that there's no VGA card installed. I don't know if this is an incompatibility between my particular ARK card and the board or if there's more to be said there, but the board seems perfectly happy with a Trio64. I'll take a look at it tomorrow, but for now I'm glad that it's working again and mostly back to the way it should be!
I was sure it is a rail between the two slots since their pins are connected serially with basically nothing between them.
If the first slot works but the second doesn’t then it is a link in there.
I believe Feipoa mentioned the same issues with Ark1000vl.
Ark1k is much more picky compared to S3 trio64.
The later worked on basically every board i put it on.
