Hi guys, another Voodoo3 repair attempt thread. I got this card in a sad state as non-working. It was missing the bracket, the heatsink, the 3 capacitors on the right and the one next to the feature connector.

But it's working, Glide included, and no stability issues so I thought it's worth the effort.
The issue I'm having is bad output with "trembling" characters. It's related to the resolution/refresh, for example the BIOS/POST screen looks only a bit blurry, while in the DOS mode the problem is worse and apparent.

This video demonstrates the problem, it might be too compressed by the hosting site but it still accurately shows what the characters look like. If anyone wants to see another recording or photo please let me know.
https://imgur.com/dwKSB0o

I did solder the 4 missing capacitors and while I was at it I changed the other 4 electrolytic as well. Also the computer/monitor/power/cables etc are irrelevant. The card has the same behavior in a completely different environment and, the opposite, another identical card works fine in the test system.

So, any ideas what might be causing this? Any suggestions for actions?