iMac Pro Intel Xeon W 3.2GHz (8 core) Vs Intel Xeon W 3GHz (10 core)

[KalanHowse]

In comparison how do both of these CPU’s perform? They are the chips in an iMac Pro.

CPU 1: Intel Xeon W 3.2GHz (8 core) Turbo Boost 4.2GHz
CPU 2: Intel Xeon W 3GHz (10 core) Turbo Boost 4.5GHz

My understanding of Intels Turbo Boost technology is as follows, please correct me along the way if I am wrong...

Depending on the TDP of a CPU it will dynamically increase the base clock speed, at that point the power consumption will increase and the CPU will have a higher temperature. In direct correlation with the cooling the Turbo Boost clock speed will either stay at an increased speed for a short or longer period of time. When the CPU has reached its maximum TDP the CPU will then clock down as low as it needs (or to the base clock speed) to maintain a healthy temperature and within power consumption contraints.

Only 1 or at most 2 cores can have their base clock speed increased, which means that single core applications can make use of higher Turbo Boost frequencies. As applications can make use of more cores the Turbo Boost frequency will again slowly decrease to stay within the set TDP. Does this mean that when all 8 or 10 cores are firing away that the base clock speed will reach thermal limits? Or is there still room in the thermal overhead to Turbo Boost a core or two just slightly faster?

So what does this mean for me?

Am I correct in saying that when using the 3GHz CPU that single core applications will perform faster than the 3.2GHz CPU due to a higher Turbo Boost clock speed (4.5GHz vs 4.3GHz) and multi-core applications on the other hand will then perform faster due to 2 extra cores despite the slower base clock speed? It may be obvious on paper but it may perform differently in actually computing performance.

Thanks for your help and any extra knowledge that is shared.

 

[now i see it]

Anything that can use all cores is going to throttle down the frequency off of turbo. You'll never see turbo speeds under those circumstances.
For 3D test rendering and fluid simulations, the more cores the better for overall speed. I don't know if you'd be able to tell the difference in real world use between a 3.2 vs a 3.0 ghz processor. I do know you'd definitely save time and notice the difference using a 10 core machine vs an 8 core during rendering & simulations even though the clock speed is a tad slower.

The 10 core costs a lot more than the 8 core. Intel prices their chips based on value and customers value their time.

But if your apps can't use all those cores- they'll just be sitting idle all the time.

 

[SDAVE]

Apple uses special binned Xeon W's in the iMac Pro that is underclocked.

The sweet spot is 10core imo in terms of performance/value and it's worth it.

If you can find the deals for $3999 for the 8 core (there were some a month or two ago) then I would snag that instead.

 

[KalanHowse]

Anything that can use all cores is going to throttle down the frequency off of turbo. You'll never see turbo speeds under those circumstances.
For 3D test rendering and fluid simulations, the more cores the better for overall speed. I don't know if you'd be able to tell the difference in real world use between a 3.2 vs a 3.0 ghz processor. I do know you'd definitely save time and notice the difference using a 10 core machine vs an 8 core during rendering & simulations even though the clock speed is a tad slower.

The 10 core costs a lot more than the 8 core. Intel prices their chips based on value and customers value their time.

But if your apps can't use all those cores- they'll just be sitting idle all the time.

Thanks for your response and input...

My workload utilises both single core and multi cores. A healthy single core frequency is pretty important which is why I was undecided with the two, and of course the 10 cores are going to sing away when they’re put to work.
[doublepost=1521450413][/doublepost]

Apple uses special binned Xeon W's in the iMac Pro that is underclocked.

The sweet spot is 10core imo in terms of performance/value and it's worth it.

If you can find the deals for $3999 for the 8 core (there were some a month or two ago) then I would snag that instead.

Do you happen to have any of those models? I’m pretty convinced with the 10 core now.. as I’ve seen a few Turbo Boost results and tests over the past day or so...

Luckily I have an extremely great connection with a business here in Australia and will be purchasing through them soon. They’re an Apple Retailer who also offer a 3 year warranty and will service/fix the Mac at no cost.

 

[SDAVE]

Thanks for your response and input...

My workload utilises both single core and multi cores. A healthy single core frequency is pretty important which is why I was undecided with the two, and of course the 10 cores are going to sing away when they’re put to work.
[doublepost=1521450413][/doublepost]
Do you happen to have any of those models? I’m pretty convinced with the 10 core now.. as I’ve seen a few Turbo Boost results and tests over the past day or so...

Luckily I have an extremely great connection with a business here in Australia and will be purchasing through them soon. They’re an Apple Retailer who also offer a 3 year warranty and will service/fix the Mac at no cost.

https://www.ifixit.com/Teardown/iMac+Pro+Teardown/101807

Look here.

It says:

Intel Xeon W-2140B (Skylake, 14 nm—likely an underclocked W-2145 to keep the temps in check), 3.2 GHz CPU with Turbo Boost up to 4.2 GHz, paired with what could well be a standard LGA 2066 socket

So it definitely seems replaceable along with the RAM.

However, I assume you need to put in the 'B' version in for 12/14/18 cores to replace the one that's already in there so it doesn't overheat. However, wouldn't be surprised if non 'B' versions work.

 

[KalanHowse]

https://www.ifixit.com/Teardown/iMac+Pro+Teardown/101807

Look here.

It says:



So it definitely seems replaceable along with the RAM.

However, I assume you need to put in the 'B' version in for 12/14/18 cores to replace the one that's already in there so it doesn't overheat. However, wouldn't be surprised if non 'B' versions work.

Hmm, I know of Apples started “Up to Turbo Boost 4.xGHz”... just not the real time frequency in short and longer periods of use.