maybe just try flashing the bios using atiflash to a 6870 bios
heres a guide you might find useful:
ALL THE FILES NEEDED 6870:
==6870 BLACK BIOS MOD 940/1150==
1) Run GPU-Z and back up your GPU BIOS.
2) Insert a USB flash drive.
3)Format your USB as FAT32
6) Now select the "Create a DOS startup disk" check box, you will then get the option of choosing the files that
make the USB bootable.
7) Choose the folder that is called "USB BOOT" then select the start button.
8) This process takes a bit of time and will blank your flash drive.
9) when your flash drive is prepped extract/Copy the files:
-old.bin (the one you backed up just to be safe, rename it if you need to)
-Barts.bin (this is an AMD OEM 6870 stock clock BIOS)
10) restart you PC and go into the BIOS menu select your USB as primary hard drive.
11) restart and you PC should boot into the atiflash.
12) type DIR to see whats in the USB you should see all the files.
13) you can type "atiflash /?" to see all the available switches but you only need to use 2-3 at most for this.
14) type "atiflash -ai 0" to get a readout of your primary card. "atiflash -ai 1" will be your secondary card if you
are running a crossfire configuration.(handy if you need to distinguish).
15) type "atiflash -p 0 biosname.bin" (atiflash -p 0 xfx.bin)
16) if it does not allow you to flash type "atiflash -f -p 0 biosname.bin". -f forces the flash.
17) if neither of these work type "atiflash -unlockrom 0" then repeat step 15 or 16
18) it will take a few seconds to complete and ask you to restart, press "Ctrl,Alt,Delete" together.
19) Go into your BIOS menu and select your HDD as primary hard disk again.
20) You may get windows detecting a new device and may be asked to restart.
21) Go into CCC and select default clocks in Overdrive and your clocks should now be reading 940 core and 1150 memory.
22) I suggest this is only done with a reference designed card. You may have a variant with a different fan perhaps wait for the manufacturer to release a OC version with the same PCB etc.
ENJOY YOUR NEW DEFAULT CLOCKS.
The link above is broken so:
take your pick from that lot! Edited by Misso - 6/5/11 at 5:35am