Graphics ATI BIOS Tweaking help required

I want to mod an ATI card to change the standard sync rates so it will work with a fixed rate monitor. Anyone know of any tutorials/sites where I can find the info - so far all I can find are ones to mod SE/Pro's etc for performance. I know it can be done because I'm trying to do the same as www.ultimarc.com do with the ArcadeVga card - but I'm trying to use a CAD monitor.

 

I wouldn't have thought the BIOS would help there, more OS but then none of this rings any bells I'm afraid. I'd imagine you'll need to edit the BIOS which you do by saving it to disk and then reflashing once edited. That's very risky stuff, certainly be sure you keep the original BIOS safe, have a PCI gfx card on stand by and set the BIOS to give PCI gfx boot priority. Best of luck.