AMD Budget Gaming Computer - 700$ and lower

I'm trying to build a gaming computer that will be able to play BF3, MW3, Diablo 3, WoW, on medium range setting.

It will need to include a Monitor that will allow me to hook an xbox upto it with an HDMI cable. Not sure if that will work or not, but wither way I need to be able to hook an Xbox up to it.

I'm also planning on having 2 monitors, only one for right now but down the road I wanna buy a second monitor.

Budget: 600-650 (maybe 700 dollars if it cant be avoided)$ has to include a monitor. I plan on upgrading the computer slowly overtime. I want it to be decent, not use an insane amount of power (dont want a huge power bill) I want it to last as well.




HERE is the build i've came up with: I really wanna get the price down on it if possible without sacrificing alot of quality.

PCPartPicker part list: http://pcpartpicker.com/p/gzeJ
Price breakdown by merchant: http://pcpartpicker.com/p/gzeJ/by_merchant/
Benchmarks: http://pcpartpicker.com/p/gzeJ/benchmarks/

CPU: AMD Phenom II X4 965 Black 3.4GHz Quad-Core Processor ($89.99 @ Newegg)
Motherboard: ASRock 970DE3/U3S3 ATX AM3+ Motherboard ($77.55 @ Newegg)
Memory: PNY XLR8 8GB (2 x 4GB) DDR3-1600 Memory ($42.99 @ Newegg)
Storage: Western Digital Caviar Blue 500GB 3.5" 7200RPM Internal Hard Drive ($62.99 @ SuperBiiz)
Video Card: XFX Radeon HD 6770 1GB Video Card ($109.99 @ Amazon)
Case: NZXT Tempest 410 ATX Mid Tower Case ($55.99 @ Amazon)
Power Supply: SeaSonic 520W ATX12V / EPS12V Power Supply ($68.00 @ Newegg)
Monitor: Dell ST2220L 21.5" Monitor ($148.98 @ Newegg)
Operating System: Microsoft Windows 7 Home Premium SP1 (64-bit) ($89.98 @ Outlet PC)
Total: $746.46
(Prices include shipping and discounts when available.)
(Generated by PCPartPicker 2012-09-04 18:52 EDT-0400)