Here is a revised PC setup, based on the higher total budget of £951:

Harddrive - Seagate Barracuda 7200.11 500GB SATA II 7200rpm 16Mb Cache 11ms 300Mb/s - £46

Motherboard - Asus P5N-E SLI 650I Motherboard DDR2 PCI-E Gigabit LAN - £56

Ram - DDR2 800 - Corsair 4GB Kit (2x2GB) DDR2 800MHz/PC2-6400 XMS2 Memory Non-ECC Unbuffered CL5(5-5-5-18) Heat Spreader Lifetime Warranty - £52.99

CPU - LGA775 package - Intel Quad Core Q6600 95Watt G0 Stepping (This is the one that Overclocks) 4 x 2.40Ghz 8Mb Cache 1066 FSB Quad Core Processor - £117

This retail boxed processor version includes an Intel reference heatsink and fan. This increased the warranty of the processor to 3 years as long as this heatsink is used.

PSU - Coolermaster eXtreme Power 650W PSU - £54.43

This PSU is Intel ATX 12V v2.01 compliant which is important. When getting a PSU also make sure it has 2 PCI-E 6pin power connectors as many high end graphics cards need them both. Also make sure there are at least 2 12V rails to give system stability.

Graphics Card - XFX 9800GTX 512MB DDR3 Dual DVI TV Out PCI-E Graphics Card - £184.99

Very powerful graphics card for the money. This one should easily run any current game, and those released over the next year.

DVD-RW - Pioneer DVR-115DBK 20x DVD?RW Dual Layer Internal IDE Black Bare Drive - OEM - £15.74

Case - Thermaltake VA3000SWA Tsunami Dream Black Aluminium Case With Window No PSU - £70.90

120mm case fans at the front and rear, plus the clear sided version also has a 90mm fan to draw air into the case directly over the CPU. I've got this case (as does JT) and it is a great case. Nice and quiet too.

OS - Vista Home Premium 64-bit - £58.75 (or Vista Ultimate 64-bit - £107.75)

Total price: £656.80 inc. VAT

Monitors
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SAMSUNG SM245B 24" 16:10 LCD TFT with 5ms Response time, DVI, 1000:1 Contrast Ratio. 1920 x 1200 - £289.05

Add in the price of the monitor and it comes to just under your total budget at £945.

This new setup has a much more powerful graphics card, Stronger PSU, similar ram to before but slightly cheaper different brand with long warranty, plus I've added a SATA DVD writer to the list and the Vista OS into the price.

If you were not going to include a monitor into the cost of your total system build, then if I were building this system the only things I would consider upgrading further would maybe be the motherboard and the PSU.

The ultimate motherboard to get at the moment is the Asus Striker II Formula 780i, but that would set up back £167.43. It can overclock the Q6600 I've included in this setup to over 3.4GHz though (with the right heatsink) and is the current gamers choice. But if you were opting for this then an even bigger PSU of at least 700W would be recommended.