This sounds like SATA/RAID driver issues. Using the 780i SATA/RAID drivers caused me reboot after reboot, even during Windows installation. The 790i drivers work flawlessly from the start.
Despite all of the trouble I've had with this board, I must say I'm now rather happy with it. After overclocking it and getting the voltages set up properly, it's been working like a charm. This is not a board for anyone intended to run stock settings, as it may be entirely unstable (as it was for me). Now that I'm running it at 1333 FSB, it's working like a charm. No reboots during use, no problems booting. I still don't intend to buy another MSI motherboard anytime soon (and I'm very weary of any driver produced by nVidia), but after enough tweaking, this board can certainly run well.
Perhaps other people are having more luck with it now, like myself?
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