Computer build help

Hey guys i am building my very first computer build i have saved up about £550 pounds but that included a moniter at 89.99. here is what i have put together i would like you please to see if it is all compatable or suggestions of what i could switch for etc for better bang per buck.

here are links to my build it is all from ebuyer

Case: Casecom Black Mid Tower Case £18.88 http://www.ebuyer.com/product/115479

Ram: OCZ 2GB (2x1GB) DDR3 1333Mhz £47.80 http://www.ebuyer.com/product/132911

PSU: Coolermaster 460W eXtreme Power Plus £39.54 http://www.ebuyer.com/product/150596

DVD drive: Sony AD-5240S £15.81 http://www.ebuyer.com/product/170014

HDD: Western Digital WD5000AAKS 500GB £39.76 http://www.ebuyer.com/product/124228

Moniter: Acer X203 20" Widescreen £89.97 http://www.ebuyer.com/product/193681

Graphics card: XFX HD 5770 XXX 875Mhz 1GB GDDR5 £145.70 http://www.ebuyer.com/product/190734

Motherboard: Asus M4A785TD-V EVO £70.81 http://www.ebuyer.com/product/169532

CPU: AMD Phenom II X2 550 Black Edition 3.1GHz £68.88 http://www.ebuyer.com/product/166518

Total: £537.15 this will leave a bit left over for extra case fans cool lights etc .

Ok and thats it. is that my best bang/buck ratio? this computer is mainly for gaming i would like to be able to play most games on full on the moniter i have chosen. but this computer will also be used for normal surfing and a bit of video editing. thanks guys and advice would be helpfull.

overclockers are s***

ok thanks i will buy the OCZ 500W now as it is only a couple of pounds more. about the Athlon i looked and as i am mainly gaming the phenom would be better and better to overclock? what do you think

^ Well you should take a look at the benchmarks and reviews of those CPUs before coming to a conclusion about them...
IMO the X3s - Specifically the 435 and 440 are the best value in terms of gaming...
http://www.tomshardware.com/review [...] ,2545.html
http://www.tomshardware.com/review [...] ,2452.html
http://www.tomshardware.com/review [...] ,2416.html

And also as for overclocking, I do accept the Unlocked multipliers of the Black are an advantage but overclocking with these CPUs isnt difficult either...