GPU: $94.99 Will be getting a second quickly if not at the same time
SAPPHIRE 100245L Radeon HD 4850 512MB 256-bit GDDR3 PCI Express 2.0 x16 HDCP Ready CrossFire Supported Video Card - Retail http://www.newegg.com/Product/Prod [...] 6814102810
CPU: $279.99 How high could this be easily O.C.'d?
Intel Core i7 920 Nehalem 2.66GHz 4 x 256KB L2 Cache 8MB L3 Cache LGA 1366 130W Quad-Core Processor - Retail http://www.newegg.com/Product/Prod [...] 6819115202
1) on the amd build drop the 4870 X2, at the moment it is the worst buy ever for two reasons, two 4890's cost the same amount as one 4870 X2, and the DX11 cards coming out around October where one GPU is as powerful as a 4870 X2 while being cheaper and using less energy.
2) you will see no performance difference in single threaded apps between the i7 @ 2.66ghz and the P2 955 @ 3.2Ghz so why spend $40 on a cooler which you could spend on a better graphics card.
3) on the PSU, I think the PCP&C 750w is cheaper and will still hold up the same cards that the corsair can.
No, AM2 processors worked with AM2+ sockets which supported AM2, AM2+, and AM3 processors, LGA 1366 will only support i7's and only about 5 different processors so there isnt much in the way of a processor upgrade path.