Okay thanks. I'll try the 2x 6core workstation. I think ~1min could be possible. I looks like the time has a linear correlation to the clock speed and the number of the threads is a multiplier.
E6850 Core 2 Duo @ 3.00 Ghz, 2 cores, 2 threads
time 14:35min
calculated time @3GHz, 4 threads: 7:18min
Core i7-4790 @ 3.6GHz, 4 cores, 8 threads
time 2:55min
calculated time @ 3GHz, 4 threads: 6:40min
core i7 @ 4GHz 4 cores, 8 threads
time 2:40 min
calculated time @3GHz, 4 threads: 6:46min
core i3-560 @3.3GHz 2 cores, 4 threads
time 7:30min
calculated time@3GHz 4 threads: 8:15min
If we had more data, the calculated time could more precise but it is good enough to answer my question
