cool job, organizing a failed group buy, postponing best group interests by 2 weeks at the end and getting free 66+ BTC for all that!

Oh ya bunch of whiners.

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It basically comes down to a limitation of Windows 7. What the specific limitation is, I don't know. But Windows 8 allows 1 more GPU to be detected and mineable. So if you install 13.1 driver on win7 and get 4 GPU working, you will get 5 GPU working on win8. Win8 is also annoying though in that you can't install "older" drivers, some of which allow an additional GPU mineable on top of that. The catalyst installer manager simply won't show the display driver installer option. SO. Here we go.

Install windows 8.
Wipe any previous GPU drivers off with amd_cleanup_util_1.2.1.0.exe (google it) if you have installed them before.
Install 13.1 plus OpenCL included with it. Personally, I only installed display driver, opencl sdk, and the hdmi driver because I dont like seeing stuff without drivers. None of the other stuff is required.
You will now have 5 GPU working with one with an error code 43 inside the Device Manager.
Open 12.6 and install only to the point where it extracts stuff into C:\AMD\Support\. Do not actually install drivers. We just need to extract.
In device manager, right click the errored GPU -> Properties -> Driver tab -> Update Driver -> Browse my computer for driver software -> Let me pick from a list of device drivers on my computer -> Have Disk -> Browse -> Navigate to C:\AMD\Support\12-6_vista_win7_64_dd_ccc_whql\Packages\Drivers\Display\W76A_INF and select either .inf file (it doesn't seem to make a difference) -> OK -> Should only have one device listed under "Model". Hit Next.

It should now proceed to downgrade from 13.1 to 12.6, which is the highest version driver that allows an extra GPU. You screen may flicker MANY times, and your device manager may appear to freeze/hang. Just let it do it's thing. It may take upwards of an hour or longer. You may get a BSOD too. Just go with it. If you're coming on 2 hours or longer, try doing a hard reset. You -should- now have all 6 GPU installed OK in device manager and detected in OpenCL. If not, reboot again (just in case).

If this doesn't work, well, I don't know what to say. This is just the solution I was given. (Well, actually, I was recommended the special 7970 release driver, but I was worried it wouldnt work with 13.1 opencl)

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