If you are not running a RAID, do you have it turned on in the bios?
Some boards have two controllers and probably need drivers for both, but not necessarily
RAID. It may be an AHCI driver that is needed, depends on the motherboard.
The Nvidia drivers I was referring to are not video drivers, but some motherboards have Nvidia chipsets and need additional drivers, or at least that how it appeared during some of the early Win 7 installs. If your motherboards have Intel chipsets or AMD, these drivers are not necessary.
You might try turning off whatever you can in the bios and make sure to unplug any devices you can to see if you can get past the driver issue. If you still have a workable OS, you might see if you have a Panther directory and look for setupact.log.