could someonehelp me build a pc for less than £300

[r4king11]

im trying to build a pc for under £300, i already can get a psu(500w) it is in my pc now snd this is a very old pc (about 5 years) and i can salvage a couple parts such as psu, disc drive, wi-fi card, card reader and 250gb hard drive.
so could you please give some suggestions on what components to get

 

[batuchka]

Wat sort of 500W PSU is that and also what use, etc - suggested format
http://www.tomshardware.com/forum/261222-31-build-advice