Could be a BIOS issue. My guess would be a corrupt BIOS bin file (either on their server or your download) or a bad flash.
Proper BIOS Flashing procedure:
From DOS
Download the BIOS bin file and BIOS flash program from manufacturer's web-site to a newly full-formatted floppy disk.
1) If OCing, reset to default
2) Clear CMOS (some say do it after flashing only, others insist on both)
3) Flash BIOS, *If fails: REFLASH, do not REBOOT until successful!*
4) Clear CMOS
5) Boot, enter CMOS Setup, load "optimized defaults"
6) Save and reboot
7) Enter CMOS Setup and re-enter your custom settings
8 ) Save settings and reboot
From Windows:
Install your manufacturer's "Winflash" program and either download the proper BIOS bin file, or have "Winflash" download the proper file.
1) From a reboot, Reset OCing parameters to "default"
2) From "winflash", flash BIOS
3) Verify successful flash
4) Shutdown computer
5) Clear CMOS
6) Boot, enter CMOS Setup and load "optimized defaults"
7) Save and reboot
8 ) Enter CMOS Setup and re-enter your custom settings
9) Save settings and reboot
Never, ever power down during a Flashing Proceedure!
Good luck with your trouble shooting! If you believe that it is BIOS conflict with your vid-card... notify the manufacturer! Unfortunately, I would suggest redownloading the BIOS update onto a New FULL-Formatted floppy disk (Best on a known stable machine) and reflashing your machine, make sure you either "save" your exhisting BIOS, or keep your successful "F4" on the same floppy disk.
This incident shows why you shouldn't flash your BIOS unless it corrects a problem that you are having, or supports performance parameters, or "base micro-code" (CPU parameters). These changes are almost always listed in the BIOS bin "change log".
*edited for clarity