specing a system - help required

[firestrike]

I am going back to university so I could do with a new computer. It will be used for CAD, Photoshop, Revitt, SketchUp and 3dsmax. I am struggling to spec a small form factor system, I am a bit out of date now and I have never done a SFF system before.

I have a budget for around £650, to include :
Case
PSU
Processor (q6600? possibly overclock)
Graphics card (radion 4850?)
Hard drive (About 750GB)
RAM (4gb)

I will use the dvd drives from my existing system. i was thinking about having two hard drives in the system (second to come from my current com(250gb))to allow me to have a back up of important documents.

I think that’s everything but it probably isn’t . Thanks for any help you can give me everyone.

 

[firestrike]

thanks for all the replies. After having a look through them ive come up with a rough spec below. I dont suppose someone would mind having a quick look through it please.


Samsung SpinPoint F1 1TB SATA-II 32MB Cache - OEM (HD103UJ) £76.99
(£90.46) £76.99
(£90.46)
Powercolor ATI Radeon HD 4850 512MB GDDR3 TV-Out/Dual DVI/HDMI (PCI-Express) - Retail £99.99
(£117.49) £99.99
(£117.49)
GeIL 4GB (2x2GB) PC2-6400C5 800MHz Black Dragon DDR2 Dual Channel Kit (GB24GB6400C5DC) £44.99
(£52.86) £44.99
(£52.86)
Lian-Li V350B Aluminium Mini-Tower - Black £76.99
(£90.46) £76.99
(£90.46)
Akasa AK-P040FG8-BKUK 400W Green Power 80+ £43.99
(£51.69) £43.99
(£51.69)
Intel Core 2 Quad Pro Q6600 2.40GHz Guaranteed to run at 3.00GHZ (1333FSB) - Retail £105.99
(£124.54) £105.99
(£124.54)
Gigabyte GA-G33M-DS2R Micro ATX (Socket 775) PCI-Express DDR2 Motherboard £59.99
(£70.49) £59.99
(£70.49)
Sub Total : £508.93

Total : £610.86

I am not sure how powerful i would need the PSU to be. I am also still curious about the shuttle systems though they do seem a bit limiting and expensive. ohhh and 1 more thing, what is the reliablity of the radeon drives like now as ive heard a few problems? am i better sticking with nvidea