How to Modify Your HD2900 BIOS Clock Frequencies by Hex File

[Don Quichote]

First try got a black screen after flashing with a modified Bios of my Pro.

After learning something about Hex-Editors , I got it to work like this:

modified Bios as I need

went into cmd and found out checksum with atiflash (atiflash -cf bios.bin)

opened Hex-editor and searched for some empty space (00 00 00 00)

entered what i need to get to my checksum ( e.g. if i get a checksum for the orig.bios of 0x8B00, but my modified file has 0x8A9B; I overwrote some zeros with 65 (0x0065) and as result got again to a checksum of 0x8B00)

Hope I explained it right, as I dont´t really know what I´m doing here. But after editing to the correct checksum, I even don´t need the -F option to flash.

I´m now running my Sapphire 512 MB Pro with Bios 2D 400/400 @ 0,9V, 3D 793/927 @ 1,2 V.

3dmark06 runs up to 850/1000
Crysis runs up to 793/1000 (over 793 core some strange flashing when smoke appears)
Hellgate an NFS Pro Street would both run the core up to 850, but doesn´t allow the VidRam to run more then 927

Perhaps I could get it higher with more power, but as I´m running stock cooler I think 793/927 ist nice for me.

Forgot to mention: runnig Vista DX10