Windows needs to install driver software for your Kernel Mode Driver Frameworks service?

6+ hours later and I'm mostly back working, but with one niggling problem...

On boot up, I'm now getting a "Found New Hardware" - "Windows needs to install driver software for your Kernel Mode Driver Frameworks service". Locate and install doesn't do anything (big surprise). I'm suspecting this is something to do with AHCI now, so I'll give the background...

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Laptop: XPS 1330 w/Vista Home Premium (updated to SP1), 250GB, 4GB RAM

I don't reboot very often; I mostly just close the lid and let the system go into standby (I wait for disk/fan activity to stop before putting the laptop in a bag). Last night, when I shut the lid, the system ran for 10 minutes before I gave up and turned it off (I tried reopening the lid, but the screen stayed blank, so eventually I just held the power button down to power off).

This morning, the laptop wouldn't boot. I could see it would give a BSOD, but would cycle so fast, I couldn't see the error. The system would then reboot and suggest running "startup repair", which would run, but didn't help. I tried doing a "system restore" - some restore points would complete, but still wouldn't boot. Some restore points I tried would give me a "System restore failed due to an unspecified error. Cannot create a file when that file already exists". I tried getting to a command prompt and doing a "chkdsk/f" - no help. I also tried safe mode and "last known good configuration". All to no avail.

I figured out to to turn off automatic restart after error. That allowed me to see that the BSOD error was "A problem has been detected and windows has been shut down to prevent damage to your computer", look for viruses, try chkdsk/f, blah, blah - and then "stop 0x0000007B"...

The stop error led me to the Microsoft article on AHCI (http://support.microsoft.com/kb/922976)

I turned off AHCI in the BIOS. That also required disabling the Flash Cache. When I saved those settings, the laptop would boot up fine. Problem is, I never changed those settings and as best I can tell, the default for this laptop is to enable AHCI, so what changed to cause the problem???. I then did the regedit to enable AHCI support and then changed the BIOS settings back, rebooted and it seems to run fine, other than the driver messages (which I can't tell keeps anything from working).

I hadn't installed any software or windows updates recently - the last had been back on 7/30/08 (KB890830). The laptop had been running fine since then, so I'm confused as to what caused the initial boot problems and what this driver message means now.