Try flashing one from the TPU VGA BIOS Collection. LINK
I can definitely see the difference.
Hi, my graphics card seems not to be supported by this software, it's a Sapphire HD 6670 1GB DDR3. When i open its BIOS it says "GetOverDrive"...
Haven't you tried flashing it with this BIOS? http://www.techpowerup.com/vgabios/95750/HIS.HD6850.1024.101229.html
It's exactly your same vcard.
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