cpu usage at vray

[nino anurogo]

Sir, my new cpu i7 6700 k when render can't reach its full speed. Its only run 99% at 3.9 ghz onstantly from build lc prepass then render. Anybody have an idea ?

[Dimitris Tolios]

99% is full speed...certain micro-tasks in the background, say, you moving your mouse, having the resource monitor running, or other processes that outside of your control all-together might be eating up that .5% or more of your CPU...

 

Don't forget that the resource manager is rounding up/down to the closest 1%.

[nino anurogo]

99% is full speed...certain micro-tasks in the background, say, you moving your mouse, having the resource monitor running, or other processes that outside of your control all-together might be eating up that .5% or more of your CPU...

 

Don't forget that the resource manager is rounding up/down to the closest 1%.

 

But 6700k supposed to be run at 4.2 ghz not 3.9 ghz like picture above. I have checked the power management and set to high performance cpu. Then bios setting the turbo boost has enabled too. My mobo gigabyte z170 hd3.maybe my processor has a bug in the microcode ?

 

Thank you Sir

[Dimitris Tolios]

Again, you over-analyze it.

 

What really happens is that your Mobo is running its BLCK bus (CPU Chipset) at 99Hz instead of 100Hz. Maybe it is a power saving setting, maybe it is something you tweaked and you did not know, maybe...regardless, t he CPU is really running 40x the BLCK at base speed, and 40*99Hz = 3.96GHz. It is common, many mobos run 1Hz up or down, just typically Windows don't report it as such and people don't care to notice and scrutinize.

 

3.96GHz is practically 4GHz ... and that is the base clock the 6700K runs at. 4.2 is the "Turboboost" speed, thus intel and everybody selling the processor describe it as such:

 

Intel ARK: up to 4.2GHz - clearly stating the 4GHz base clock.

Amazon: Intel Core i7 6700K 4.00 GHz Unlocked Quad Core Skylake Desktop Processor

Newegg: Intel Core i7-6700K 8M Skylake Quad-Core 4.0 GHz

 

etc

 

The "turbo" frequency is a dynamic overclock that the CPU applies to one or more cores based on the current temperature of the CPU and the Watts being pulled. Even with "super-duper" cooling it won't turbo all the cores at 4.2GHz for prolonged tasks like rendering. Not your 6700K, nor mine, like all the Core CPUs before it. If you do have good cooling, you can overclock it manually and have all cores being at 4.2 or 4.5GHz, but it won't do it from the factory - ever.

Edited October 1, 2016 by dtolios

[nino anurogo]

Again, you over-analyze it.

 

What really happens is that your Mobo is running its BLCK bus (CPU Chipset) at 99Hz instead of 100Hz. Maybe it is a power saving setting, maybe it is something you tweaked and you did not know, maybe...regardless, t he CPU is really running 40x the BLCK at base speed, and 40*99Hz = 3.96GHz. It is common, many mobos run 1Hz up or down, just typically Windows don't report it as such and people don't care to notice and scrutinize.

 

3.96GHz is practically 4GHz ... and that is the base clock the 6700K runs at. 4.2 is the "Turboboost" speed, thus intel and everybody selling the processor describe it as such:

 

Intel ARK: up to 4.2GHz - clearly stating the 4GHz base clock.

Amazon: Intel Core i7 6700K 4.00 GHz Unlocked Quad Core Skylake Desktop Processor

Newegg: Intel Core i7-6700K 8M Skylake Quad-Core 4.0 GHz

 

etc

 

The "turbo" frequency is a dynamic overclock that the CPU applies to one or more cores based on the current temperature of the CPU and the Watts being pulled. Even with "super-duper" cooling it won't turbo all the cores at 4.2GHz for prolonged tasks like rendering. Not your 6700K, nor mine, like all the Core CPUs before it. If you do have good cooling, you can overclock it manually and have all cores being at 4.2 or 4.5GHz, but it won't do it from the factory - ever.

 

Okay then i will oc all core to 4.2 ghz. I think its enough for my purpose. Thank to your enlightment.

My cooler is very base.

[nino anurogo]

Maybe it is because thernal throttling

My cooler is cooler master hyper 212x turbo.

I could affordd the noctua nh d15 but im affraid the noctua will bend my thinner skylake cpu green substrate

[Dimitris Tolios]

Again,

I think your read too many "horror" stories online and you over-think it.

 

1) the CPU is doing fine. It is not throttling - it won't do 4.2GHz on factory settings, regardless of D15 or H100 or Phase Change cooling. You need to manually overclock it to have more than 1-2 cores doing 4.2GHz.

2) the 99Hz vs 100Hz frequency on the mobo won't make any tangible difference. A BIOS upgrade/downgrade might end up with 99 or 101 BLCK, depending on version.

3) the NH D15 won't bend your CPU or mobo. It has a well thought bracket that receives all the lateral forces. The only way to damage your components is over-tightening the screws. Cause it is logical...a 1kg cooler needs at least 1000 N/m (lets say 100kg for laymen) of force on each screw, x4 screws, right?

[nino anurogo]

Okay then i will overclock the all four cores at 4.2 ghz. Thats enough for my purpose and hsf i think. Hope cm 212 could handle this.

Thank you for the enlighment Sir