if you can go to about 420 this is what I recommend. however this is without the operating system. if you need an OS then some corners will have to be cut or you will have to cough up some extra dough (bout 80-100 pounds, which as you can see will also put a big dent in the parts you can get with 400). This system is very similar to what I have myself, so I can tell you from experience that it is good stuff and will handle anything you can throw at it. its got lots of space to upgrade too if you wish to do so in a year or two. drop in a new CPU/graphics card and you are all set!
Its essentially the same thing just 200mhz slower. that can be easily remedied by going into the BIOS and setting it to run 200mhz faster (or more if you want). I have my Athlon II 250 X2 (the original 200mhz faster one) happily running at 3.85Ghz at the moment. If you need help with that I will be happy to.
also, this PSU was what I originally would have picked, but that one was on sale. Its also modular so you have a neater case and has an extra 100W to play with. It was only 8 pounds more with the discount. but if 8 pounds is important, here is the original
hardware
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