Xeon Ivy Bridge-EP: Core Count vs Frequency.

[luci5r]

Guys,

I have a question. I'm building a dual Xeon workstation based on the new E5-2600 V2 series processors that dropped today. Primary CPU task is rendering (CGI).

The E5-2650 V2 supports 8 Cores / 16 Threads @ 2.6Ghz Base / 3.4Ghz Turbo.

The E5-2660 V2 supports 10 Cores / 20 Threads @ 2.2Ghz Base / 3.0Ghz Turbo

Every other aspect of the two CPU's is the same.

The price difference is $200 per CPU, which means $400 total. Speaking in totality, that is, 2 Chips:

Is it better to have 4 less cores / 8 less threads but faster frequency? Or are the extra Cores/Threads at a lower frequency worth the extra $400?

I don't know which one is better - less cores/threads at faster rate or more cores/threads at slower rate.

The answer will also tie into the comparison between E5-2640 V2 which has the same 8 Cores / 16 Threads as E5-2650 V2 but operates at a lower 2Ghz Base / 2.5Ghz Turbo - but can be had for $600 less then E5-2650 V2. The question there is - is the faster 2.6Ghz Base / 3.5Ghz Turbo for same # Cores/Threads worth the extra $600?

Can't decide. Need help.

Thanks!

 

[Zodiark1593]

For rendering (and if your time == money), Buy the 10 core Xeon!!!

 

[gleep9]

The rendering performance difference will be ~5-8%, if that's worth $400 to you then go for it. Number of cores * clock speed = rendering perf (roughly), so you can compare all of the xeon parts using that formula. When I compared all of the V2 chips the performance per dollar only got worse as the core count went up, so it comes down to how much is your time worth?

 

[SunnyD]

The rendering performance difference will be ~5-8%, if that's worth $400 to you then go for it. Number of cores * clock speed = rendering perf (roughly), so you can compare all of the xeon parts using that formula. When I compared all of the V2 chips the performance per dollar only got worse as the core count went up, so it comes down to how much is your time worth?

Totally my superlurker!

Now back on topic.

Basically you want more cores with as much clock as you can get. Rendering scales pretty much in multiplicative fashion with cores, so it makes linear clock speed gains is less of an issue.

 

[luci5r]

The rendering performance difference will be ~5-8%, if that's worth $400 to you then go for it. Number of cores * clock speed = rendering perf (roughly), so you can compare all of the xeon parts using that formula. When I compared all of the V2 chips the performance per dollar only got worse as the core count went up, so it comes down to how much is your time worth?

So essentially the 10 Core / 20 Thread chip operating at a lower frequency will actually render faster then an 8 Core / 16 Thread chip operating at a faster frequency. First of all that's good to know - because I really didn't know if that was the case.

That said, I'm not sure if ~5-8% is worth $400.

My initial budget per chip was roughly $1,250, so about $2,500 total. Quite initially I had actually selected the E5-2640 V2 as the chip I was going to go with; but this was based on "rumored" spec & prices at CPU-World. All that changed yesterday as actual specs & prices came in slightly different.

The E5-2650 V2 sits very comfortably in my budget & purpose, at $1299 a chip, coming in at $2599 total. I think I would need more then a relative 5% - 8% difference to invest another $400 into the chips.

I can see what you're saying; if I use your formula:

E5-2650 V2
8 (Cores) * 2.6Ghz (Base) = 20.8
8 (Cores) * 3.4Ghz (Turbo) = 27.2

E5-2660 V2
10 (Cores) * 2.2Ghz (Base) = 22
10 (Cores) * 3.0Ghz (Turbo) = 30

The 10 Core Xeon definitely outperforms the 8 Core, but marginally. I'm not sure that difference of 20.8 vs 22 or 27.2 vs 30 is worth an additional $400.

Totally my superlurker!

Now back on topic.

Basically you want more cores with as much clock as you can get. Rendering scales pretty much in multiplicative fashion with cores, so it makes linear clock speed gains is less of an issue.

I'm not clear on what you're saying; I do understand wanting more cores with as much clock -- but that's where xx50 & xx60 are conflicting as xx60 gives me 4 extra cores / 8 extra threads albeit a much lower clock then the xx50.

The $400 price difference is also an issue, where the actual % difference could help decide.

Thanks guys.

 

[ShintaiDK]

It depends, if you render 24/7, then the 10 core. However every time you do something that doesnt use all the cores. The 8 core will be faster.

 

[luci5r]

It depends, if you render 24/7, then the 10 core. However every time you do something that doesnt use all the cores. The 8 core will be faster.

That's a good point!

The machine is *not* exclusively rendering only. There is some other stuff going on as well. Web design / development, Dreamweaver, Photoshop, Audio/Video Editing, Vegas, Premiere. Aside from this a lot of Excel & FoxPro. Also Gaming (RTS Only) - StarCraft2, CoH2, Civilization, etc.

A lot of CGI Development aside from rendering - Maya, ZBrush, RealFlow.

There will be points where I will rendering 24/7 for certain periods - when the projects development is over & it's time to Render. But that render will eventually end & other things will ensue.

--

The more I look at it, I don't believe the $400 investment is justified. Between the xx40 & xx50 there are other differences besides clock speed (Cache, QPI) so the price difference there is justified. But I don't think the difference between xx50 & xx60 is quite justified in my case.