The 80ns memories should work but you might experience some minor graphical corruption (wrong pixels and such) occasionally, especially in elevated temperatures.

Tiido wrote on 2020-06-27, 12:39:

The 80ns memories should work but you might experience some minor graphical corruption (wrong pixels and such) occasionally, especially in elevated temperatures.

I hoped not but I imagined it... let's try this, I've an ATi Wonder 28800-5 card with two soldered TMS44C256-80N and two socketed identical model but also with four HY534256S-70 ram on the remaining four sockets. I suppose someone added the 512Kb using faster 70ns ram that should run @80ns as the soldered right? What if I change these four modules with the above ones and replace them with the 70ns?

Yeah, those 70ns parts on the ATI card are running at 80ns, so the extra speed is getting wasted. You could definitely do the juggle.

Tiido wrote on 2020-06-27, 12:53:

Yeah, those 70ns parts on the ATI card are running at 80ns, so the extra speed is getting wasted. You could definitely do the juggle.

Strangely switching those rams both cards doesn't work ok.. the Oak seems to reboot sometimes and shows the initial bios line; there's a Vesa jumper on board maybe it would need that or maybe the bios is limited to the initial ram (four of those above 70ns modules) while the ATi seems to not pass the checkit video test.. I'm not sure about the 80ns quality that came from an old pc but the 70ns I put back into the ATi always worked ok.

I guess the 80ns chips aren't ok, or at least one of them isn't if the video test fails. The known working 70ns parts not allowing things to work is stange though, there shouldn't be any additional conf necessary for extra memory either.

Tiido wrote on 2020-06-27, 17:18:

I guess the 80ns chips aren't ok, or at least one of them isn't if the video test fails. The known working 70ns parts not allowing things to work is stange though, there shouldn't be any additional conf necessary for extra memory either.

Maybe I'll look for the exact memory modules online. Sure it's strange and I checked correctly their installation key point. Maybe has something to to with the bios config. Not that this was a great vga, in Windows I saw the usual slowness of the lacking acceleration but in 3DBench I was above the 14.x fps value while the TVGA 9000A went down to 13.x and the GD5429 up to 15.6/15.8 depending if in real mode or not.
But I suspect the GD5429 is using zero wait state as a user suggested me and I think it's why is so unstable..