I have also managed to get windows 8 running via EFI boot on my early 2011 MBP.
Neither the AMD 6750m or the Intel HD3000 GPU are working - neither drivers can start the device. (tried both latest drivers off the net, and bootcamp rubbish drivers)
Having the Intel enabled will blue screen during device driver loading at startup.
Windows 8 runs fine, using Basic Display Driver (unknown GPU in use, assuming AMD as it is used during the EFI stage).
Played with enabling the Intel device in the EFI shell - managed to boot windows 8 3 times WITH Intel GPU enabled, but black screened and no output on external monitor. Cannot confirm if using the first EFI shell command below does enable the HD 3000, but I think so. Just doesn't configure resources in a useable fashion. 😐
Can use EFI shell commands (converted from grub) such as metatechbe detailed a page back:
mm 0000020054 0b -w 1 -pci (Activates Intel GPU, supposedly)
mm 728 1 -io (Switch select - this has no feedback, completes ok)
mm 710 2 -io (Switch display - this drops the EFI shell to a black screen - expected, as Intel HD3000 doesn't seem to have resources)
Reboot, tried:
mm 740 2 -io (Switch DDC, no feedback, completes ok)
mm 750 0 -io (Power off AMD, screen drops to black, EFI halted. Seems to work as expected, but as Intel is not running it is not very effective. 😉)
I am trying to find some reasources somewhere that may allow me to configure the Intel HD3000 and disable the AMD GPU in a way that would allow the Intel HD Drivers to work in windows 8 via EFI. This could take a while. I bought a lemon in this Early 2011 MBP. 😠
Anyone know where to find any info on configuring PCI devices? Metatechbe? Anyone?
UnnDunn: what model MBP do you have that you can see the HD3000 running ok in device manager?