S2469, POST/boot: VGA only, no DVI???

Archived from groups: alt.comp.periphs.mainboard.tyan (More info?)

[I posted a slightly different message about this before.]

Does anyone know what determines VGA/DVI output during POST/boot?

I've got a Tyan S2469 (aka "Thunder K7" ) board. It used to boot fine with a
single DVI cable. But since I had some hardware problems (PSU, probably), now
the boot comes up only in VGA. If I connect both DVI and VGA, it only appears
on VGA. After booting I *can* get it to go into DVI mode by starting Xwindows
(I'm running Linux). But the standard text modes (720x400, etc) won't work on
the DVI connector.

Other people have reported problems like this in Windows, where DVI only
becomres active after booting, but I have not seen any answers.

Does anyone have ideas? I've tried different monitors, cables and video
cards. I've also reset the CMOS on board and flased the BIOS again. But
there don't appear to be any BIOS settings for this.

Thanks!
Richard