Hmm you can get a better computer for 850£.
Intel Core 2 Duo E8400
ASUS P5QL-E
OCZ Reaper DDR2 1066MHz 2x1GB
Saphire Radeon HD4870 1GB
Seagate 500GB
LG 22x6x16 DVD-RW
Antec 300 Gaming Case
PC Power & Cooling 650W
Logitech G11
Logitech G9
Acer 20''
Logitech X-540
That is what I'm getting after Christmas and it's going to be just about 850-900£. I know it doesn't have a ubber monitor but eh... IF you keep some parts of your old computer like the HDD and Case and maybe Monitor, you can get a pretty decent computer for 850£.