DIY PC draft spec- advice appreciated

[hardwaren/a]

Basically I want a computer that will play games, not necessarily on high spec but you know...playable. Games like crysis or ARMA 2 for instance. Also, all this has to be done for a budget price,around £450. ATM I have come up with the following.(the links underneath each component lead to Novatech, a UK company and are not 'dangerous' to view and are their only for you to read if you want to help you tell me if you see any problem with the spec).

Motherboard/CPU/Memory: (as this will be my first build i have decided to go for a pre-assembled board, CPU and memory. I am aware that the RAM pre-installed is not that great but having upgraded RAM in the past i know that i can easily change that as and when.
Intel Quad Core Q8300 - 4Gb DDR2 800Mhz - Intel G31 Motherboard
http://www.novatech.co.uk/novatech/specpage.html?MBB-834G

Hard drive/ Optical drive- I already own a decent enough hard drive and optical drive that I can salvage from my old PC.

Case:CoolerMaster Elite 330 Midi Case
http://www.novatech.co.uk/novatech/specpage.html?CM-E330

Graphics card:ATI Radeon HD4850 1024MB GDDR3
http://www.novatech.co.uk/novatech/specpage.html?NOV-48501
( The game that happens to come with this card, if you saw it from the link has no bearing on my choice)

Power Supply:OCZ ModXStream Pro 500w Silent SLI Ready ATX2 Modular
http:// www.novatech.co.uk/novatech/specpage.html?OCZ-M500 (http://www.novatech.co.uk/novatech/specpage.html?OCZ-M500)

I will probably install Win7 on this computer but that is still to be decided.

Please tell me what you think and if i have made a massive error or you have a criticism of the spec then feel free to make a note in your reply.

All reply's are welcome and thank you in advance.

[hardwaren/a]

bump bump bump

[RecT]

Looks good to me

[Dave P]

That's basically a more up to date version of what I'm running, some of the later levels of crysis you wont be able to run at high settings probably.

(though that may depend how you play... I use speed mode to run down the machine guns then throw explosives everywhere and shoot anything moving or flamable [yes thats still viable in delta mode (god I love crysis)], which tends to make things chug a bit).

But overall, you can run crysis at relativly high settings and not worry about it, and of course anything like modern warfare 2, you wont even blink at running it. :)