Huge (40%) speed discrepancy between 3770K nodes

[jackbird]

I'm running my first real job with two 3770K render nodes I put together recently, and one of them is absolutely destroying the other one despite them theoretically being the same speed:

 

EDIT - these are frames from a turntable animation - I would expect more or less consistent times throughout.

 

 

On the slow one, something strange is going on in Task Manager. The new Win8 panel shows 60% CPU utilization:

 

 

But the old-style Details panel shows 99% utilization for the same process:

 

 

The slow machine is being rated with a Performance Index of 0.61 by Backburner, so 60% CPU utilization seems about right.

 

The fast machine is running Win7, and the slow machine is running Win8, and they have different motherboards, but otherwise they're basically identical.

 

Has anyone seen this before? Any idea how to start troubleshooting?

 

EDIT: CPU temperature is 52-53C while rendering

Edited August 1, 2013 by jackbird

[jackbird]

OK, I now know that it actually is running slow:

 

 

But I still have no idea what to do about it. The BIOS is set to defaults on both motherboards, and I'm completely out of the loop as to how to manually set multipliers, etc. correctly.

 

Or is this some kind of thermal throttling thing?

[jackbird]

So I found a utility called Throttlestop that allowed me to set the CPU multiplier from software (without interrupting my render ). Temperature changes were immediate and dramatic to the tune of 20C, but things are nice and fast now.

 

If anyone knows what any of this was about, or why it happened, or a better way to fix it, please chime in.

 

[Fooch]

we had issues w ours. 4x boxes were constantly slow compared to a lot of the same spec'd versions. plus we bought 16 at the same time ..

Our resident tech guru finally figured it out.

Check your cpu fan for the slower boxes. Is it touching the processor completely

[jackbird]

Given the way the 3rd/4th-gen core CPU fans mount, what sort of scenario would produce incorrect contact?

 

Also, the CPU temps were in line with the fast machine once I got the multiplier/turbo mode up.

[numerobis]

Is the bios up to date on both machines? It is possible that:

a) you need to update the bios for Win 8

b) you need a newer bios with 3770K support (i'm don't know the board model and how old it is)

 

If not, a bios update should solve the problem.

Otherwise you could set the multiplier manually in the bios/efi, keeping the other settings (voltage etc.) on default/auto values, should be easy. (if the board supports this)

 

These CPU-Z screen are both under full load?

[jackbird]

yes, both under full load. Slow machine is a Biostar H77MU3, which says "Win 8 Ready" on the box.

[numerobis]

ok a H77 should at least be ready for the 3770K... and for a H77 i think there are not many settings you can change in the bios concerning the cpu speed. The latest bios is more than a year old.

 

So i think there is not much you can do, maybe...

-check the bios settings (cpu ratio, turbo, speedstep)

-reinstall the mainboard drivers

-reset the bios

-reinstall windows

[joelmcwilliam]

Two different systems?

 

Please name all parts of both systems.