Ok, can you give me some more system specs to work with.
What is your
PSU make, model and rating.
How heavily loaded is your
PSU, how many optical drives and HDDs
Have you properly connected the molex +12V connector to the plug at the back of the 6600GT?
And also, do you have a dedicated line from the
PSU to the 6600GT, or is the line from the
PSU to the 6600GT shared with the hard disk? ie, some molex lines have 2 or 3 connectors on it, while the 6600GT should be the ONLY thing on its cable.
Also what are your chipset drivers?
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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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