What CPU to use for ABC, and why?

[Dirk Broer]

My answer to the question "What CPU to use for ABC, and why?" is - All of them. Because every cycle counts.

But given the fact that running 6 systems 24/7 is already the limit, powerbill-wise, I want those 6 CPUs to be as effective as possible.

[Dirk Broer]

Which AMD Quad would be the best choice for the ABC@Home project, and does it pay to use a hexa- or octocore?

Scores per day per core:
Phenom II X4 980: na
A8-3820: 593.7 (Linux 64)
A8-3870K: na
FX-4100: 1317.7 (using Linux 64, Windows 64 brings you 779.9)
FX-4170: na
FX-4300: na
FX-4350: na
A10-5700: 1,040.9 (Linux 64)
A10-5800K: na
A10-6700: na
A10-6800K: na

Pretty inconclusive about our quaddies. Best scoring AMD CPU appears now the FX-8350 with 1,502.5 per core per day (=12,020 per CPU/day). The i7-3770K is only slightly better at 2,089.0 per thread/day (=16,712 per CPU/day) and twice as expensive to purchase (though less expensive to run 24/7).