First of all, you didn't inform us which driver versions you are using. Which PBE you are using for modified your bios? I suggest using PBE 1.6.2 instead 1.6.6, PBE 1.6.2 will copy strap 1750 to above (more stable based on my experience). And don't forget to use Crimson ReLive Edition Beta for [Suspicious link removed]pute driver. And the last thing, patch your driver signature, so the system will recognize your modified bios.