2:43AM
Jinxy, What graphics card are you using?
Check out a thread that I started not too long ago regarding similar issues. The nightmare of FireWire versus graphics cards is real. I'm living in it right now.
I'm thinking graphics as well.
a) update to latest graphics drivers
b) update from dell for latest chipset drivers
c) Part of optimizations for audio in any Windows is reducing visual aspects. Look at optimizing for performance more than visuals.
d) evaluating fw, I did plenty bios changes, not allowing core parking, removing dynamic overclocking and things like that. I also reverted to legacy fw drivers in W7 - and machine worked much more smooth.
Even back in XP I had such issues, not using FW, but opening popup menues made a click in audio. Removing shadows on popup menues fixed it.
So a workaround might be to change visual aspects of W7.