CPU: Intel i5 3570K - $229.99
http://www.newegg.com/Product/Product.aspx?Item=N82E16819116504
MOBO: ASRock Z77 Extreme4 LGA 1155 Intel Z77 HDMI SATA 6Gb/s USB 3.0 ATX Intel Motherboard - $134.99
http://www.newegg.com/Product/Product.aspx?Item=N82E16813157293
GPU: GIGABYTE GV-N670OC-2GD GeForce GTX 670 2GB 256-bit GDDR5 PCI Express 3.0 x16 HDCP Ready SLI Support Video Card $399.99
http://www.newegg.com/Product/Product.aspx?Item=N82E16814125423
RAM: G.SKILL Ripjaws X Series 8GB (2 x 4GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Desktop Memory Model F3-12800CL9D-8GBXL - $45.99
http://www.newegg.com/Product/Prod [...] 6820231428
PSU: CORSAIR Enthusiast Series TX650 V2 650W ATX12V v2.31/ EPS12V v2.92 80 PLUS BRONZE Certified Active PFC High Performance Power Supply - $89.99
http://www.newegg.com/Product/Prod [...] 6817139020
CASE: COOLER MASTER HAF 912 RC-912-KKN1 Black SECC/ ABS Plastic ATX Mid Tower Computer Case - $59.99
http://www.newegg.com/Product/Prod [...] 6811119233
COOLER: COOLER MASTER Hyper 212 EVO RR-212E-20PK-R2 Continuous Direct Contact 120mm Sleeve CPU Cooler Compatible with latest Intel 2011/1366/1155 and AMD FM1/AM3+ - $34.99
http://www.newegg.com/Product/Product.aspx?Item=N82E16835103099
HDD: Western Digital Caviar Blue WD5000AAKX 500GB 7200 RPM 16MB Cache SATA 6.0Gb/s 3.5" Internal Hard Drive -Bare Drive - $69.99
http://www.newegg.com/Product/Prod [...] 6822136769
SSD: Crucial M4 CT128M4SSD1 2.5" 128GB SATA III MLC 7mm Internal Solid State Drive (SSD) - $89.99
http://www.newegg.com/Product/Prod [...] M4&x=0&y=0
OS: Microsoft Windows 7 Home Premium SP1 64-bit - OEM - $99.99
http://www.newegg.com/Product/Product.aspx?Item=N82E16832116986
Your taste in cases are probably different to mine so feel free to choose another one. But generally the HAF series from CoolerMaster provides great airflow, which is what you want unless you're into silent builds.