optimal CPU for running several (6 and more) single thread applications simultaneously

[freymart]

I have a very specific problem right now, for which I need the ideal CPU. I want to run several instances (at least six, sometimes up to 8) of a pure single thread software. This software does simulations, so the application is always on full load.

The system will run almost 24/7 doing simulations. After doing some research I figured that the usual benchmark are meaningless for me. Obviously Intel is much faster if running a single thread applications and it also superior for multi thread optimized applications.

But if I have the scenario that I described above I assume that a AMD FX-8350 eight core CPU would be superior.

Any help would be appreciated

best regards Martin

 

[Madn3ss795]

Yes, FX8350 would be superior here ( It has 8 actual threads after all. i7 only gives 4 actual and 4 virtual threads ), unless you can go for 500$+ workstation CPUs.

 

[freymart]

Thank you for varification. It took me some time to find the right word for what I was looking for. It is called multitasking if I am right.

Intel is much faster in isolated single thread applications. However I cannot find a benchmark for multitasking single thread applications ,i.e., running 6 in parallel and then benchmarking how good they perform in summation.

So I assume the performance would be something like this:


4 multitask single thread applications: i7 (4 cores / 8 virtual)
5 multitask single thread applications: i7 (4 cores / 8 virtual)
6 multitask single thread applications: i7 (4 cores / 8 virtual) / FX (8 cores) not sure here!
7 multitask single thread applications: i7 (4 cores / 8 virtual) / FX (8 cores) most likely AMD!
8 multitask single thread applications: FX (8 cores) obviously AMD

But obviously if I am concerned about the volume throughput regarding my simulations 8 parallel instances will yield the highest throughput and will always beat fewer instances.

 

[freymart]

Maybe an older AMD 6 core (i.e. AMD Phenom II 1090T) is even superior to the i7 when it comes to 6 parallel instances? Very difficult to judge and I have no idea why there is not suitable benchmark out there which covers my issue?

 

[Madn3ss795]

Yes it's called multitasking. AMD have been leading over Intel in multitasking for a few years ( when the 2 compared CPU are in the same price range ). They have always had CPUs with more cores but weaker single-core performance.

Indeed an occa core FX will yield better performance when running 8 threads parallel. Basically an FX performs better in any tasks can utilize all 8 threads it has. A test made by the local tech forum in my country:

( "rendering time(s) - lower is better" ), E3 1230 can be treated as an i7 without IGP.

 

[freymart]

Great information thank you a lot. So the test was for 8 threads? 4x3dStudioMax + 4xVray? And I assume that it consisted of pure rendering maybe raytracing? That would be great as raytracing in those programs is very similar to the CPU heavy simulation I want to perform.

What is good to see is that overclocking is huge here, so it would make sense to OC the 8350 to 4,6 or 4,8 GHZ in my case. However I am a little concerned about the durability of a OCed system if running 24/7.

In order to find the RAM that I need I just have to run one simulation and check how much it consumes some time into the simulation and then make sure that I have enough RAM to have 8 run parallel. Or 7 if I want to normally work with the machine.

 

[Madn3ss795]

Yes vray is optimized for raytracing. As far as OC option goes, it depends on the motherboard and the CPU cooler you'll get, too.

 

[freymart]

Is it too much off topic to ask you those OC related questions here? As I assume you could give me a valuable answers

 

[Madn3ss795]

I'm not that of an expert in OC-ing, but yea, just ask.

 

[freymart]

I want a low noise system So I am not sure what cooler would be best to OC to 4,8GHZ on the FX 8350. Will a good silent Air Cooler do the job or do I need something like a 80i or Kraken X60? And regarding RAM I never understood the ideas behind RAM OC and why it is necessary if I only want to OC the CPU?

I don't want to go extreme by any means so I seek a OC solution to go to 4,6 or 4,8GHZ stable. What would be standard stuff here regarding mainboard/RAM/cooling? Any ideas?

I have to do very long simulations for 4 to 6 month straight for my PhD studies so 200MHZ more can same me weeks in the end. However as a single simulation only takes half a day, it would not be "game over" if the machine crashes once.

 

[Madn3ss795]

Yes I think the H60 or Kraken X40 ( X60 sounds quite overkill ) should do. Fans are PWM controlled so noise shouldn't be a big problem. As for motherboard, a AM3+ board with 6+2/8+2 phases power design is required. I'd recommend Gigabyte 970a-ud3 as the cheapest option, then gigabyte ga-990fxa-ud3 as the price goes up.

Doesn't find many advantages from OC-ing RAM, thou.

 

[qbsinfo]

lets look at a direct comparison between single and multi threaded performance between the cpus using the same bench:

the i7 is approx 24% faster than the 8350 (312/252)

the 8350 is ~10% faster than the i7 (1504/1363); a 34% difference in performance. its a common belief that hyper threading is approximately 30% of a "real core" in performance. and that seems to be; since half the i7 is 70% slower that would lend to a ~35% performance difference (70/2).

so when running 4 cores or less the i7 would be 24% faster, after that it will start losing ground to the 8350. and without running the figures, since it been a long night, it looking like ~7 cores.

 

[freymart]

@Madn3ss795: Ok so I'll go with the X40 then. What standard RAM would you recommend? And yes budget is an issues as my research fund does not cover a new computer and I have to pay it upfront by myself.

@qbsinfo: So I wasn't off too much with my inituial gues that at 7 and more parallel single thread applications a FX 8-core beats a i7. Good to know that a virtual core is roughly 30% of a real one performancewise in multitasking.

 

[Madn3ss795]

Just get the 970a-ud3 then. As for RAM, Any kit with heatsink would do, since you're going to run your software 24/7 after all. I'd recommend G.SKill RipjawX or Corsair Vengeance.

 

[freymart]

Ok so this would be my setup:

• 
  AMD FX8350
  Gigabyte 970a-ud3
  Corsair hydr H60
  Noctua NF-P12 PWM
  8 GB kit Corsair Vengeance DDR1866
  Samsung SSD 840 Pro 256GB
  Antec Threehundred Two 
  be quiet! Pure Power L8-CM 530W ATX 2.31

Does this looks reasonable as a complete low noise system?

I assume that I need DDR1866 RAM. Do you think that a 430 Watts power supply would be sufficient?

 

[Madn3ss795]

Eh, FX CPUs don't have IGP. you'll need a discrete VGA card. Even the cheapest one would do, thou.

Also, H60 isn't a cooler with performance/price ratio. Air coolers are better at this price range. Any links to the website you use to get those prices from?

 

[freymart]

I always search via geizhals.at.

Hi, I still have a PCIe radeon that I'll use.
I could also use my old air cooler: http://geizhals.at/ekl-alpenfoehn-gross-clockner-rev-b-84000000018-a570261.html together with the low noise Fan that I posted.

Overall price for the list above would be 723 EUR = 950 USD

 

[Madn3ss795]

That's good news. Your current cooler is not a bad one, we can just skip the H60 and put on it better fans instead. This cooler is quite large, however, so you should get low profile ram sticks instead, in case the cooler block ram slot(s). Corsair vengeance or Kingston HyperX sticks should do. Whether a lower ( 430w ) psu is enough or not depends on the vga you already got. If it requires just 1 or 0 PCI-E power cable then the 430w model can still do the job here.

 

[gamerk316]

To answer the OP: Probably a quad. Why? Because given how much your applications will be getting paged out by other system level tasks, and given how its unlikely all six applications are using high workload threads AND will have all their data available at the same time, its highly unlikely that all six applications will be able to run at the same time. I doubt you'd see any performance increase going from a i5 to a FX. (Given the IPC differences, its possible you could see a performance loss)

 

[Madn3ss795]

I think he OP was pretty clear on how to get 6/7/8 tasks run at the same time.

 

[Cazalan]

8GB sounds low for running 8 render threads. Isn't that usually a memory intensive application?