Hi, I wonder if someone could give me a bit of advice and tell me what sort of graphic card I should search for gaming on Mac Pro. I am thinking to buy used Mac Pro and display and I want something fast enough for different applications including gaming for next four years. I believe something like quad core 2.66 or 2.8 with at least 6 gb RAM and 512 mb graphic card will do. What is difference in speed between RAM of DDR2 and DDR3? Can I say that 10GB DDR2 is equivalent of 6GB DDR3? And which graphic card is better; Nvidia or ATI and whats the difference between those two? Also about displays; should I go for brand new LED cinema or previous generation one? As far I see the difference is only with iSight built in and better contrast ratio. Is it worth it then? Excuse my knowledge but being with mac few years I should know more than that however it doesn't make any harm to ask experienced folks up here. Thanks in advance.