Help with black screen flashing - Vista Ultimate

Hey all, I stumbled across this forum site when I was looking for help with a problem I've been having on my desktop Vista machine.

I am running:
Vista Ultimate 32-bit
Intel Core 2 Duo E6600 (2.40 GHz overclocked to 3.38GHz)
NVidia GeForce 7900 GS
8GB of RAM (video editing and photoshop)

Vista rates my computer's performance at 5.7 (Processor and Primary Hard Disk being the two lowest factors)

Every time I plug in or remove a USB device or a CD/DVD, my screen flashes black a few times. It's not a huge deal because it comes up with properly recognizing the USB device or disk, but it's really annoying!

I have tried the following fixes:
all drivers are up to date, as per DriverMagician software
disabled UAC control to stop switching to safe desktop
disabled TMM
changed power settings to high performance
disabled file indexing

Any others with this problem and or with different suggestions for what I might try to fix this?

Thanks

Does it still happen if you force use of the base VGA driver (and reboot)?

BCDEDIT /SET VGA ON

Thanks for the reply.

I tried that, rebooted the computer, and my screen was automatically set to 640x480.
I plugged in a portable external hard drive, and the dread black screen flash happened again.

I also tried uninstalling the video card and letting it find the drivers again, and the black screen still happens.

Any other ideas on what might be the problem?

Edit to add: Just now, I have also reset my computer's settings to the original settings, so no overclocking, no messing with any of that. Still no joy.