How long has it been running? I've bought a couple of rigs off ebay in the past, but I tend to filter out anything that was built a couple of years ago, since there's a chance I'd have to replace something sooner rather than later. But then, if you factor that into the price...
Don't really know price-wise. I could spend £600/£650 and get the same pieces but with a 7950 and build it myself. Is it just what you list, or are you including a case? If you're including case then you could aim for £500, since you'd get people who are too scared to build themselves a PC looking at it (even without a HD). Otherwise, you're looking at selling to the enthusiast market, who would do what I just did and cost out a better machine at a little more.
Pixieking
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ASUS P8P67 Evo - Intel i7 3770k - 2X4GB GSkill RipJaws X DDR3 1600 - HIS 7950 IceQ - Creative XtremeMusic Soundcard - NZXT Phantom 530 - Thermaltake Toughpower XT 675 - Win7 x64
