Where can I build my own deskt

[matthew]

I know there are several websites where companies such as Dell and Asus will allow consumers to pick and choose what kind of processor they want, etc. Do any of these companies allow you to do this with desktop PCs? I'm looking for a decent gaming rig, but don't want to spend thousands of dollars just for a brand name such as Alienwares (which look dumb anyway). I don't think I have the computer know-how to build my own PC from scratch, which is what I would rather do.
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