Hey, I have always used generic and low-end psu's and it has never effected the performance of my machine.
I have a 3700+ and a 7800gt and my aspire 500watt $39 psu runs the system great.
However many people have been talking to my about the importance of a good psu.
How important is having a brand name psu?
If I bought a good $100-$200 brand name psu, would I notice a performance upgrade?