Probably the latest one,
6 Core - 3.5GHz processor (default) boostable to 3.9GHz
16 GB DDR3 ECC (default) upgradable to 64GB
Dual AMD 500 FirePro
1526 stream processors
384-bit-wide memory bus
240GB/s memory bandwidth
2.2 teraflops performance
Hope that gives you an idea.... it costs around 4K dollars, with 4K you'd get a double the power custom Beast...