Also if it's mainly Call Of Duty that you enjoy, and your current pc is happy with all the other jobs you ask of it, have you considered the (ooo this is going to open a can of worms!) xbox360 ?? Especially if you have a HD ready TV. In my opinion you really need about double that before you can start seriously looking for a decent gaming machine. If you want a monitor as well in that budget..good luck. Also you don't say if it's CODE 1 or 2 you are playing. If it's 1 then you will probably be able to upgrade your current machine. I used to run it happily on an AMD 2600 with a GeForce 4600ti and 512mb ram. However if it's the second game then you need serious hardware if you want to run it at full spec, ideally either a x1900 or 7900 series GFX card.
The Xbox running on a HD tv will look as good as nearly any sub £1000 pc due to the following:-
1) Microsoft looses money on them, they are subsidised quite heavily. 2) They are designed purely for games., and as such have very specific components 3) because the hardware is constant the writers can push it too the limit without having to worry about it running on certain variations.
Pop down to your local games store and ask them if you can have a look at COD2 running on one. Most will obligue if it's likely to get a sale.
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