I'll recommend you a system.
AMD Phenom II X4 965 BE + Asus M4A785T-M = $442
Team Elite 2x 2GB DDR3-1333 Kit RAM = $172
Western Digital Caviar Blue 500GB SATA = $74
Sapphire HD5770 1GB = $245
Andyson F650 650W PSU = $119
CoolerMaster 341 mATX Casing: $59
LG DVD Writer = $34
Multi Card Reader 3.5" Internal = $15 (from any random shop)
Others:
Add extra $10 to upgrade from mATX CoolerMaster 341 to ATX midtower
CoolerMaster 310 w/ side window
Cooling:
Case fans: CoolerMaster Elite 341 can accomodate 4x 120mm case
fans. $44 for 4x CoolerMaster R4 LED 120mm fan (from
CyberActive)
OR
AVC F1225B12V high performance 120mm fan, 4x for $52 @ Sim Lim
Tower L1 ASK Electronics
CPU
Cooler:
CoolerMaster Hyper TX3 (for CM 341 mATX casing), add $39. Pay
additional $15 to upgrade the stock CM TX3 92mm fan to AVC
Hydraulic Bearing 92mm high perfomance, from UVnium. As this cooler
supports dual-fan push pull, you may consider investing in a
matched pair of AVC 92mm fans to achieve push-pull
configuration.
OR
CoolerMaster Hyper 212+ (FOR ELITE 310 ONLY, ELITE 341 CANNOT
FIT), add $59. AVC F1225B12V fan can also be used on this cooler.
This cooler support push-pull fan mounting also, so you may want to
purchase a matched pair of AVC F1225B12V fan, or purchase a 120mm
CoolerMaster BladeMaster 120 fan to match the original Hyper 212
fan in push-pull.
Other Items:
Add anywhere $150 and above for LCD screen starting from
18.5"
Add $158 for a copy of single use, OEM Windows 7 Home Premium
64-bit.