Could always reset the Q4 config files I guess and change those options one at a time to find out which one is the issue.
Incidentally, I played the Q4 demo under Fedora 7 a bit last night before I went to sleep. It's pretty good, and very fast
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Notebook: Apple Macbook Pro 13" i7 2.7Ghz (3.4Ghz max) 8GB DDR3 1333Mhz (Mac OSX 10.6.7)
Desktop: ASUS Rampage Formula X48
Intel Core 2 Quad Q9450 (Yorkfield) @ 3.60Ghz (Folding SMP Linux)
Running Fedora 15 Linux (GNOME 3)
Dual Dell 2407WFP 
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