AMD Athlon II X3 Tri Core 455 3.30GHz (Socket AM3) - Retail £67.99
Gigabyte GA-MA78LMT-US2H 760G (Socket AM3) DDR3 Motherboard £49.99
or
Asus M4A78LT-M 760G (Socket AM3) DDR3 Motherboard £49.99
Coolermaster Elite 430 Windowed Case - Black (with 500w Elite Power PSU) £64.99
OCZ Special OPS 4GB (2x2GB) DDR3 PC3-12800C8 1600MHz Dual Channel Kit £35.99
Samsung SpinPoint F4 320GB SATA-II 16MB Cache - OEM £29.99
Arctic Cooling Freezer 7 Pro Rev 2 CPU Cooler (Socket 939 / AM2 / AM3 / 775 / 1155/ 1156 / 1366) £17.99
LiteOn IHAS124-19 24x DVD±RW SATA ReWriter (Black) - OEM £14.99
Total £281.93
Saves you nearly £45.
Swaped AMD for Intel.
Case & PSU bundle.
Smaller but faster hard disk or just go with the one you put originally.
Perhaps just have a look at the RAM. The motherboard says it supports 1.5V and the OCZ are 1.55-1.65V. Should be OK as long as the RAM runs at a reasonably low voltage.
Should be fine for "a cheap pc for surfing the net and watching the odd movie" as per your other thread.
You could save another £8 getting this processor:
AMD Athlon II X3 Tri Core 450 3.20GHz (Socket AM3) - Retail£59.99
You could save a few more quid if you're happy with a dual core:
http://www.overclockers.co.uk/productlist.php?groupid=701&catid=6&subid=803