I just found my ASUS Crosshair II Formula was broken. I have requested an RMA and I'll have to wait more than one month and a half to get a replacement. Meanwhile, I found that my old ASUS Crosshair was working so I replaced the motherboard until I get the new one.
Now Windows 7 x64 doesn't boot. openSUSE 11.3 x64 does. Windows actually reboots after a flash-blue-screen even if I try to load safe mode.
I already know I can format, but I don't want for now.
The problem is that I have 5 HDDs and Crosshair II was in AHCI mode to make OS detect all 6 SATA ports. Crosshair classic has 6 SATA ports, but they are regular SATA controllers. When I upgraded Crosshair to Crosshair II with Vista, I had the same exact problem of Windows rebooting when SATA ports were set to AHCI (when set to IDE I could see only 4, as documented on the manual).
I'm sure that now, during the downgrade, the same kind of problem is occurring. When I had Vista I was able to install mobo drivers in IDE mode then run system restore in AHCI mode and let it do something about it.
Do you have any ideas? I tried disabling "Silicon SATAII controller" on BIOS but didn't help (and it still detects 5 HDDs)
Update: this is what I tried with Vista, just to be complete - http://www.avforums.com/forums/windows-7/944905-windows-7-ahci.html