i grabbed ati's x800 pro 256 mb bios from techpowerup.com. here's the filename "ATI.X800PRO.256.Samsung20.040408.bin" - released 4/8/04 & supports 2.0 ns samsung memory
i've edited the memory timings and underclocked it to 351/297 which is the stock speed of my m9800. the x800 pro bios however was missing a few memory variables. specifically, "memory refresh rate - MemRR=30" and "refresh row cycle time - tRFC=17"
i've posted the modded x800 bios here. please check my work. i used rabit1.7.http://www.angelfire.com/games5/clan_sh5/
i don't suppose you can give me a hexidecimal offset of where line 1536 is? that way, i can frankenstein the bios for others to try.