The ATI has more pixel pipelines, more core clock, and more memory. "SK33TASTIC" makes a good point. There is one upgrade that you should always spend more on. Graphics. I looked @ Tiger D. and noticed a 7900 gs ko model. It has ddr3 instead of ddr2. 20 pixel pipelines, 500 mhz core clock, 1380 mhz memory, 44 GB's per sec. bandwith. It is listed @ $134.99 but has a $20 rebate. That's a great value and would give you better performance. Good Luck.