Best gaming PC specs within £300-500?

Whats the best specs i could get for £300-500 (roughly $600-1000)? Is "The bigger the number, the better it is" true when it comes to graphics cards and whatnot?

All I know is that you need the super future tech where, this is all true, you can have MULTIPLE video cards and processors, MULTIPLE!!! We have never had that technology before, so you'd better go get it NOW!!