Hi all, I have an Asus EAH5850 (EAH58502DIS1GD5) with its standard BIOS. I'm trying to change the BIOS fan speed settings, as it spins too slow and it is very hot where I live. If I run GPU-Z v0.4.3 it gives the correct data for my card, but when I try to save the existing BIOS, GPU-Z refuses and says "BIOS reading not supported on this device". So I boot into native DOS and save the BIOS with atiflash.exe (v3.79). Now I have the existing BIOS ROM file (128KB in size). I noted the checksum in DOS. I load the BIOS file into Radeon BIOS Editor (v1.25) and it's all OK, it's the correct data and has the same BIOS checksum. I make the fan speed changes and save the BIOS to file NewBios.ROM. I boot to native DOS and check the BIOS checksum of NewBios.ROM and it matches the original checksum. Now when I try to flash it in native DOS (atiflash -p 0 newbios.rom) (or atiflash -f -p 0 newbios.rom), atiflash makes a comparison between the two cards (everything matches), but then it gives the following error and nothing is flashed: "ERROR 0F01". Anyone has any idea why it does this. I did a search but could not find a solution. Thanks a lot System details (all stock, no overclocking): Intel i5 750 Gigabyte P55A-UD3P PSU Corsair TX750 750watt RAM 4GB Corsair XMS3 DDR1600 Asus ATI Radeon HD5850 PS: I do not want to flash from within Windows as that is apparently not advisable for cards with GDDR5 memory. PPS: I read the sticky on Flashing the 4870 and that is the same method I used.