My first H110 had 2 bad PCIe slots.  But I was able to get 7 GPU mining on it.  When I got the replacement mobo, I also went from Win10 to Ubuntu, because I had another 6 NVIDIA GPU on the way.  Long story short, Linux hates me.  So I went back to Win10, and had a lot of issues with getting the mobo to not freeze up when I had more than 2 GPU connected.

After many many driver reinstalls, and windows repairs, and disabling VT-d in BIOS, and plenty of reinstalls for the mobo drivers, I have it mining stable at 6 GPU.  However, at 7 GPU, the miner would lock Windows, and I'd have to restart.  After another reinstall of the mobo drivers, it now locks at the windows load screen, when 7 GPU is connected.  But 6 GPU still work great.

I've combed through BIOS many times and I can't imagine a setting I'm missing.  However, the only thing I can think of, is that my Windows is not on a UEFI partition?  Is this a possible problem, that would be corrected by reinstalling windows a UEFI partition?

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