Please help me solve this Mac Pro 4.1 mystery.

[rueyloon]

Hello

hi, I have 2 x MacPros 5.1 (updated from 4.1) that I only use for batch processing.

One is an 2 X Quad 3.33ghz, the other is a 2 X Hex 3.34ghz.

Every single time, the 8 core outperforms the 12 core. I think there was only 1 time during a video conversion that the 12 core was faster.

My theory is that the 12 core hits the temperature limit earlier and that throttles down the CPU.
What do you think?

 

[fastlanephil]

Maybe try cranking up the CPU booster fans on the hex core using Mac Fan Control.

 

[thornslack]

Seems odd. Maybe the 12 core has a blown a rivet or something

 

[ActionableMango]

My theory is that the 12 core hits the temperature limit earlier and that throttles down the CPU.
What do you think?

I think it would be easy to test your theory with temperature monitoring software.

 

[orph]

whats the app, settings the same on both boxes?
no limitations in drive speed,ram? (gpu?)
no background apps ruining?
all cores being used?
also as actionable mango mentions check temps

 

[rueyloon]

whats the app, settings the same on both boxes?
no limitations in drive speed,ram? (gpu?)
no background apps ruining?
all cores being used?
also as actionable mango mentions check temps

Batch processing,
Various RAW to JPEG conversion, or video rendering, no background apps, all cores used (which is why I offload to these 2 computers, so I can continue to use my main one)
Temperatures reaching 80-90 celsius.

 

[adam9c1]

Look at app called TGPro to monitor temperatures.

Full version allows you to force speed of fans.

Love the app and support is fantastic.

 

[orph]

what app's for conversions?
some apps we know only use 'x' cores some things we know are drive limited some things we know prefes mater a lot.

Temperature Monitor can be used to show temps http://www.bresink.com/osx/TemperatureMonitor.html
or
macs fan control shows temp and fan speed https://www.crystalidea.com/macs-fan-control
or
HWSensors https://github.com/kozlek/HWSensors/releases shows most info

screen shot helps
doing a handbrake export on my 6c 3.33ghz my cpu stabilizes around 85c

 

[pl1984]

Is it possible you can provide the model numbers for the CPU's in each system? And the specific software you're using?

If not temperature perhaps the software cannot utilize all twelve cores? I have a Z600 with 24 threads and a Z620 with 32 threads and Handbrake encoding is the same on either (both are clocked at 2.93GHz) because Handbrake cannot utilize the extra cores in the Z620.

 

[orph]

handbrake was just an example from me rueyloon has not listed what software he uses.
(easy way to check how hot my cpu gets , dual cpu macpros run a tad hotter than single cpu so i gess his temps look tad hot but normal)
i think handbrake cpu use 6-10 cores relay depending on codec etc
the help says scales well to 6 cores then less well after
https://handbrake.fr/docs/en/latest/technical/video-encoding-performance.html
(HT cores some times dont relay count with apps like this)
this says 6-10 depending on settings/codec
https://www.reddit.com/r/Amd/comments/6t0x77/do_you_know_that_handbrake_can_only_use_up_to_6/

multiple instances of the app each doing exports for batch work tends to be the way to scale with large core counts