It's 2500 USD. I have a empathy for hcmd2, but it could be any, why?

Take a look at this page: http://www.totalgeekdom.com/?p=572

I suggest something different than TylerChris post. Unless you plan to participate on other BOINC projects, right now for WCG there's no use for GPUs. Maybe in a near future, but right now your best bet is to invest in the best CPU, which I believe is the Intel i7-2600K.

You can build your PC without a discrete graphics card and save a lot of your budget for now, and add a powerful GPU later when WCG supports them.

+1

Although, don't exaggerate the amount of watts of psu if this is the setup you're planning to build. Pick a psu from a trusted manufacturer like Corsair, Seasonic or Enermax. Then choose any >300W psu. The 2600K seems to require about 250 watts when OC'd.

Throughout BOINC-land, and even here at WCG, start small and expand only if finances allow; thus, there is no point aiming for performance-per-machine, not yet anyway. That leaves spreading performance on many optimum-cost machines, meaning the most bang for your buck, and that can only be AMD-64bit-Linux. Add GPU later, if desired (and again, only if finances allow). This scheme should get you started without burning a hole in your pocket, and without over-committing to an arrangement which may be difficult to maintain (electricity cost, hardware maintenance cost, etc).
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