Bulldozer vs Vishera vs Sandy Bridge(small comparison)

I've seen many time ppl buy "8-core" AMD CPUs, mislead by number of cores and absolutely convinced its best bang for the money, instead of 2500K or even 3570K, which have only 4 cores. I know which is better for crunching, but recently friend of mine bought 8320 CPU and put it under the high end water cooling, so I decided to run a comparison between this 8320, my old 2500K and a 8120, which he took temporarily to compare Buldozer and Vishera core arhitectures.
We settled at 4.6 GHz frequency for testing, as his MSI mobo has some issues with Visheras and 8120 is barely able to reach higher frequency. My 2500K is perfectly OK with old Noctua NH-U12 cooler, running 4.6 GHz 24/7, crunching our favorite SETI.
Beside completion times, we measured power consumption. Values, given here, are the values from wall socket, where consumption of all components, included in all systems, except motherboard, memory and CPU are excluded. So the numbers bellow are only for those three. Also, values are raw, PSU efficiency is not applied, but both systems are equipped with high end PSU, with similar percentage load, so we can assume, efficiency is close enough for both systems. Energy used per WU is based on load consumption minus idle consumption, only difference between these two.
Also, for comparison sake, I included my shiny new 3930K, running also at 4.6 GHz. But its not part of general comparison, bcs its price is way higher. Anyways, its interesting to see out how energy efficient it is, as it is rarely seen CPU, especially here and even more especially, running at such high frequency.
Test is based on running 24 MB WU tasks with most common AR lately - 0.385, in different scenarios and target is finding average time per task, wattage per task and total number of tasks per day. There are some runs for AMD CPU with different memory settings to see how they affect crunching speed. I also decided, it is need to be seen how good AMDs wil be running only 4 tasks simultanenously, as they have 4 physical FPUs - this is where "MT efficiency" comes from - its actual gain from running 8 tasks, compared with 4 tasks. For 3930K CPU, there is "HT efficiency", standing for difference with running 12 and 6 simultaneous threads(MB tasks in our case). "Average CPU time" is time for a single task, as it is written in client_state.xml file, after completion.
Actually, tasks ran are more, 36, so to not let cores being idle, when they complete some task, but only 24, same for all runs were taken into account. Some note on Intel CPUs - they uses fastest client available, SSE3 Intel. I ran tests with all available clients from Lunatics installer and picked the fastest. I also included 3930K with only 4 cores and hyper-threading enabled, to simulate 8-threaded Sandy Bridge(well, can't ignore 4 MB more cache, but life is a bitch). For AMD CPU, best client is known, not much choices to make :) I ran also AMD SSE3 client on Intel CPUs and 3930K on 4.7 GHz(just to prove it can do it and to see scaling. It can actually do 4.9 GHz with this cooling, but VRM temperature reaches 120 degrees Celsius, which is not healthy for the system). If someone needs full data, let me know, I'll post it.
Important, those msot likely to be scenarious, are made bold for easy viewing.

Here go the numbers:
AMD CPUs:
----- 8120, 4.6 GHz, 8 WUs - 1600/8, idle 93 W, load 360 W
Average CPU time: 7071.01 s, 1:57:51 , 0.51 WU/h, 12.22 WU/day per core, 97.75 WU/day per CPU package, 65.56 W/WU, MT efficiiency, 60.91 %

----- 8120, 4.6 GHz, 4 WUs - 1600/8, idle 93 W, load 310 W
Average CPU time: 5689.96 s, 1:34:50 , 0.63 WU/h, 15.19 WU/day per core, 60.75 WU/day per CPU package, 85.73 W/WU

----- 8320, 4.6 GHz, 8 WUs - 1600/8, idle 80 W, load 310 W
Average CPU time: 6862.40 s, 1:54:22 , 0,53 WU/h, 12.60 WU/day per core, 100.72 WU/day per CPU package, 53.74 W/WU, MT efficiency 62.27 %

----- 8320, 4.6 GHz, 4 WUs - idle 80 W, load 260 W
Average CPU time: 5568.81 s, 1:32:49 , 0.65 WU/h, 15.52 WU/day per core, 62.07 WU/day per CPU package, 69.60 W/WU

Memory frequency and HyperTransport speed changed(default memory speed is 1600 8-8-8-28, 2200 MHz HT):
----- 8320, 4.6 GHz, 8 WUs - Memory 1866 MHz, 8-8-8-24
Average CPU time: 6844.64 s, 1:54:05 , 0,53 WU/h, 12.62 WU/day per core, 100.98 WU/day per CPU package

----- 8320, 4.6 GHz, 8 WUs - Memory 1866 MHz, 8-8-8-24, 2600 MHz Hyper Transport
Average CPU time: 6845.57 s, 1:54:06

Intel CPUs:

---- 2500K, 4.6 GHz, SSE3 Intel - idle 59 W, load 164 W
Average CPU time: 3297.42 s, 0:54:57, 1.09 WU/h, 26.21 WU/day per core, 104.82 WU/day per core package, 24.04 W/WU

---- 3930K, 4.6 GHz, no HT, SSE3 Intel - idle 79 W, load 260 W
Average CPU time: 3217.18 s, 0:53:37 , 1.19 WU/h, 26.86 WU_day per core, 161.14 WU/day per CPU package, 26.96 W/WU

---- 3930K, 4.6 GHz, SSE3 Intel - idle 79 W, load 300 W
Average CPU time: 5519.78 s, 1:31:60 , 0,65 WU/h, 15.65 WU/day per core, 187.86 WU/day per CPU package, 29.51 W/WU, HT efficiency 16.58 %

---- 3930K, 4.6 GHz, SSE3 Intel, 4 cores + HT - idle 77 W, load 221 W
Average CPU time: 5237.97 s, 1:27:18 , 0,69 WU/h, 16.50 WU/day per core, 131.98 WU/day per CPU package, 26.19 W/WU, HT efficiency (none, bcs system refuses to boot with 4 CPU cores and Hyper-Threading disabled)

Well, conclusion is obvious. 2500K is faster than Vishera(which is faster than Buldozer) and it is twice more energy efficient. Based on electricity prices here in Bulgaria, where we have relatively cheap electricity, and prices of CPU + Mobo, able to achieve such frequencies(not counting the price of water cooling for Vishera) it will take three months 24/7 cruching to make cost of ownership of Intel system same as Vishera system. In areas with more expensive energy, it will take less. Lately, things are even better for having 2500K, as Microcenter USA gave them for 99 US bucks for a piece with store pick-up, and greater availability of 2500K second hand(btw, Microcenter Minneapolis was most messy computer parts store I've ever seen - was like post-nuclear scenery :). Unusual for US, but there is was. And maybe still is, will see again this summer). There are more good thing of having 2500K, instead on 8320. 2500K overclocks better with box cooler. 4.2-4.3 is usual range. Vishera can reach 4 GHz, but you wont like temperatures - they are very close to temperatures where most AMD CPUs fail, I wouldn't leave 24/7 like this. And one more thing. Bcs of low completion times per WU with 2500K, I find it more error prone - errors can be caught more faster and less work is lost if CPU trashes units and gives errors.
I'm happy 2500K owner for two years, and above is the prove that it is good piece of hardware, worth the money. 12K RAC average(100 units*120 credits each) from CPU is descent value.
I'm even more happy with 3930K, but as we know, it is in other category. It can go further than 20K RAC per day, which I find very impressive value for CPU. THe most impressive part it the tests with it was, that it is very close as for energy efficiency to its low end counterparts, in contrary to my expectations.
I'm looking forward to replace 2500K with 3570K, which is even more faster(around 15% expected) and more energy efficient, but its only if good deal comes around.

I hope you enjoyed it :)
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It is not very clear as I read it again.
This:

Average CPU time: 3297.42 s, 0:54:57, 1.09 WU/h, 26.21 WU/day per core, 104.82 WU/day per core package, 24.04 W/WU

means:

Average CPU time for one WU - 3297.2 s
Same, but in format h:m:s - 0:54:57
1.09 WU/h - number of WU per core for one hour
26.21 WU/day per core - this is self explanatory, above, multiplied by 24 hours
104.82 WU/day per core package - number of active cores, multiplied by above number
24.04 W/WU - doesn't need explanation
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Valuable info, thanks!

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News about SETI opt app releases: https://twitter.com/Raistmer

Actually, I've ran this r557 AP application, but for Windows, on 3930K(4.6 GHz), with and without AVX(Win XP x64 and Win7 x64). Difference in not that big, although it is significant. 4:20 hours without AVX(can be seen in my computers page even now) vs a lil bit less than 4 hours with AVX.
AFAIK, there isnt MB application for Windows, which uses AVX. Only Astropulse. And switching to Linux is not an option :)
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I don't know exactly, this CPU never ran on default frequency. But you can calculate, scaling of compeltion times is same as frequency scaling. Add some 30% to times and it will give approximate values for default 3.2 GHz(non-turbo frequency, we assume all cores are loaded) of 3930K.
Perhaps Linux apps are just better optimized.
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Actually "pure CPUs" are in the past.
Need to compare APUs now. Intel "APU" (SandyBrige is APU in AMD terms though Intel probably never called it so) and AMD APUs. That is, GPU component too.
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News about SETI opt app releases: https://twitter.com/Raistmer

In that spirit, any chance of having Intel built-in GPUs to work for SETI? You are our only hope :)
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In that spirit, any chance of having Intel built-in GPUs to work for SETI? You are our only hope :)

Hoohoo,

When is the new lunatics cpu app available with avx extensions for sandy / ivy bridge?

In that spirit, any chance of having Intel built-in GPUs to work for SETI? You are our only hope :)

Yes, already. But I need testers. So far it works only on my own Ivy Bridge :)

Hi,

My i7-3930K is running boinc on linux 64 bit (FC14).
I could test a new MB AVX version if you or anybody else have a version for linux.

(I'm currently runnig the almost a year old lunatics MB CPU & GPU and astropulse AVX for linux64.)

The system is set up to use HT (6->12 cores) but boinc CPU is limited to 50% of processors. This way i have 6 HT cores for GPU apps whenever they need CPU for memory transfer/occasional arithmetic.

--
petri33
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It will be great, if u test with 6 and 12 enabled threads, same tasks. Interestingly, on this processor, HT efficiency is almost non-existent with AP, even worse, 12 simultaneous tasks are finished same slow as two groups of 6 tasks(I turn off HT completely from BIOS - XP scheduler get confused with more than 8 cores - if 6 tasks are being run with 12 cores enabled, it does not put one task per physical core, but uses very often two logical cores of same physical core, even when there is other free physical cores. With 4 tasks on 8 cores it does make it OK). For example, this run, from first post, with 12 simultaneous tasks, where HT efficiency is 16.5%, when I ran it second time, gave me even worse result than 2 sets of 6 tasks, something like "negative HT efficiency".

Raistmer, if your Intel OpenCL application can run on Sandy Bitch too, I'm ready to test it. You may contact me on PM with details any time.
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