On that budget Intel is a pretty bad idea, any chance you or he can get a student copy of Windows 7?
Microsoft Windows 7 Home Premium 64-Bit - OEM (GFC-00599) £84.99
(£72.33) £84.99
(£72.33)
G.Skill Ripjaw 4GB (2x2GB) DDR3 PC3-12800C8 1600MHz Dual Channel Kit (F3-12800CL8D-4GBRM) £84.59
(£71.99) £84.59
(£71.99)
XFX ATI Radeon HD 4850 512MB GDDR3 PCI-Express Graphics Card £68.14
(£57.99) £68.14
(£57.99)
Asus M4A78LT-M LE AMD 760G (Socket AM3) DDR3 Motherboard £51.99
(£44.25) £51.99
(£44.25)
AMD Athlon II X2 Dual Core 245 2.90GHz (Socket AM3) - Retail £47.99
(£40.84) £47.99
(£40.84)
Seagate Barracuda 7200.12 500GB SATA-II 16MB Cache - OEM (ST3500418AS) £31.71
(£26.99) £31.71
(£26.99)
Corsair CX 400W ATX Power Supply (CMPSU-400CXUK) £29.99
(£25.52) £29.99
(£25.52)
Xigmatek Asgard Midi Tower Case - Black £26.99
(£22.97) £26.99
(£22.97)
Sony Optiarc AD-7260S 24x DVD±RW SATA ReWriter (Black) - OEM £13.99
(£11.91) £13.99
(£11.91)
Sub Total : £374.79
Shipping cost based on delivery to Credit/debit card billing address, GU2 8AU with:
FREE SHIPPING (DPD Next Day)
(This can be changed during checkout) Shipping : FREE
VAT is being charged at 17.50% VAT : £65.59
Total : £440.38
You can probably get that in budget if so.
http://www.overclockers.co.uk/showproduct.php?prodid=GX-180-XF&groupid=701&catid=56&subcat=1009 That card is still fine for 'light gaming' if you want to cut another 10 quid off.