Welcome Back SpeedRaider!

[guru]

If you are buying new the 4770k or 4690K are good choices. The 4960K should be cheaper with very similar performance. If you shop used and can get a good deal(say half of the price of 4770k) on the 2500k, 2600k or 2700k they will give good results.

I'll be out crabbing tomorrow so no new updates until Sunday.

[pinhodecarlos]

Tim,

There is memory bottleneck issues which means you need to have faster memory and bigger cache. Also you won't take advantage by having HT on the processor so you can rule out i7 and stick with an i5.
Because SOB is running candidates with exponent n=29M, you will see a big degradation in speed when you keep adding instances, this means that you need to understand on your processor if it is better to have one or two or three or four instances running. Example, I have two laptops, one Haswell and one Ivy Bridge, and I only can run on them two instances of prime95 (or LLR) but I am running RPS project with k=5 and n=4.6M. Memory is DDR3 1600 MHz. At this exponent by adding a third instance I can notice memory issues, decrease on overall output.

What people do on Prime95 project (GIMPS) is to only run 2 LL tests (these tests take like 30 days or more, not sure for now) and 2 factoring because it is more efficient to do this on a quad core machine. In guru machines I would run half of the cores with SOB and the other half on dnet...something like that....

At the end if you don't care about the best efficient way to run SOB just run one thread of Prime95 per psychical core. If you care for now the best overall option, for home users that pay electricity, is the core-i5-4690k with DDR3 at 2400Mhz, taking into consideration that fact that it is needed to make a test on how many cores you should run (for SOB, high exponents to test).

Carlos

[guru]

Tim,

There is memory bottleneck issues which means you need to have faster memory and bigger cache. Also you won't take advantage by having HT on the processor so you can rule out i7 and stick with an i5.

Carlos

Yes you don't need the HT from the i7 but the i7 does have 8mb cache vs the 6mb cache of the i5. That 2mb should make a difference in SOB.

[tim]

Thanks for the advice. I'm not finding refurb i5 4690k. I'll have to look at building. Or get back into it, it's been years. The last one I built was a Athlon xp 3000.
Too bad nobody makes a LGA-1150 dual socket mobo. Or an AM3+ dual. 16 cores on one home machine would be nice.

[tim]

Even as dual socket AM3+, it would be faster than i5 4690k not by much. From looking at mersenne.org's cpu comparison of iteration times, it looks like 2 amd 8 core processors would do about 1/4 more work than i5 4690k in the same amount of time. At a cost of more electricity. I'd still be interested if a dual mobo existed. Or better, dual lga-1150 socket.

[pinhodecarlos]

Even as dual socket AM3+, it would be faster than i5 4690k not by much. From looking at mersenne.org's cpu comparison of iteration times, it looks like 2 amd 8 core processors would do about 1/4 more work than i5 4690k in the same amount of time. At a cost of more electricity. I'd still be interested if a dual mobo existed. Or better, dual lga-1150 socket.

Don't put AMD's to run LL tests, it's a waste of time due to the fact that you can't take advantage of the avx instructions.

[tim]

AMD's . . . can't take advantage of the avx instructions.

I read that AMD FX-8350 does have avx instruction set, not avx 2.0. Has the client not been updated to take advantage of it? I have also noticed that amd chips don't do near as well as intel at sob.