Games nowadays utilize the graphics cards more than the cpu's. how heavily do you multi task? that'll determine between an i5 and i7 build? plus there is a complete guide you can use to build your new computer after you have your parts picked out
assembly guide:
http://www.tomshardware.com/forum/274745-31-step-step-guide-building
I7 build I'd go with:
case Antec Nine Hundred Two Black Steel ATX Mid Tower Computer Case-$119
cpu Intel Core i7-950 Bloomfield 3.06GHz LGA 1366 130W Quad-Core Processor -$299
mobo GIGABYTE GA-X58A-UD3R LGA 1366 Intel X58 SATA 6Gb/s USB 3.0 ATX Intel Motherboard-$209
ram CORSAIR DOMINATOR 6GB (3 x 2GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Desktop Memory Model -$189
hd Western Digital Caviar Black WD1002FAEX 1TB 7200 RPM SATA 6.0Gb/s 3.5" Internal Hard Drive -$87
psu CORSAIR HX Series CMPSU-750HX 750W ATX12V 2.3 / EPS12V 2.91 SLI Ready CrossFire Ready 80 PLUS SILVER Certified Modular Active -$149
gpu MSI N460GTX Hawk GeForce GTX 460 (Fermi) 1GB 256-bit GDDR5 PCI Express 2.0 x16 HDCP Ready SLI Support Video Card-$239
cd drive ASUS DRW-24B1ST/BLK/B/AS Black SATA 24X DVD Burner - Bulk - OEM-$23
OS Microsoft Windows 7 Home Premium 64-bit 1-Pack for System Builders - OEM-$99
Extras
Arctic Silver 5 Thermal Compound - OEM -$10
COOLER MASTER Hyper 212 Plus Intel Core i5 & Intel Core i7 compatible RR-B10-212P-G1 120mm "heatpipe direct contact" Long -$29
Antec 761345-75024-0 120mm Blue LED Case Fan-$15
About $1400-1500. You can Sli another gtx 460 later and add a ssd drive then your pretty much set
I5 build id go with:
case Antec Nine Hundred Two Black Steel ATX Mid Tower Computer Case-$119
cpu Intel Core i5-760 Lynnfield 2.8GHz 8MB L3 Cache LGA 1156 95W Quad-Core Desktop Processor -$208
mobo ASUS P7P55D-E Pro LGA 1156 Intel P55 SATA 6Gb/s USB 3.0 ATX Intel Motherboard-$179
ram CORSAIR DOMINATOR 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Desktop Memory Model -$119
hd Western Digital Caviar Black WD1002FAEX 1TB 7200 RPM SATA 6.0Gb/s 3.5" Internal Hard Drive -$87
psu CORSAIR HX Series CMPSU-650HX 650W ATX12V v2.2 / EPS12V 2.91 SLI Ready 80 PLUS BRONZE Certified Modular Active PFC Power Supply-$119
gpu MSI N460GTX Hawk GeForce GTX 460 (Fermi) 1GB 256-bit GDDR5 PCI Express 2.0 x16 HDCP Ready SLI Support Video Card-$239
cd drive ASUS DRW-24B1ST/BLK/B/AS Black SATA 24X DVD Burner - Bulk - OEM-$23
OS Microsoft Windows 7 Home Premium 64-bit 1-Pack for System Builders - OEM-$99
Extras
Arctic Silver 5 Thermal Compound - OEM -$10
COOLER MASTER Hyper 212 Plus Intel Core i5 & Intel Core i7 compatible RR-B10-212P-G1 120mm "heatpipe direct contact" Long -$29
Antec 761345-75024-0 120mm Blue LED Case Fan-$15
$1200-1300 and you can Sli the gtx 460 later if needed and add an ssd drive
**Just threw these together, can be modified im sure for better/cheaper value(hd/ssd/psu/case)**
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SSd G.SKILL Phoenix Pro Series FM-25S2S-60GBP2 2.5" 60GB SATA II MLC Internal Solid State Drive (SSD)-$144**
**all builds are before tax and rebates**