Dual CPU

[mavericks7913]

When does Mac Pro use dual CPU? Only if I use specific programs like Premier pro? I recently notice that the 2nd CPU is always hot while the other one is quite cool and I assuming that Mac Pro does not using dual CPU all the time.

 

[MarkC426]

AFAIK it will only use all cores with multithreaded applications, or if you have many programs running at once.
i.e. rendering, audio etc.

 

[orph]

only apps that can scale past the first cpu and cores on the first cpu.
some apps are not even relay able to scale past 1 physical cpu thanks to coding it seems.
see the compleat lack of scaling past 1cpu (most the time) in Premier CC
https://www.pugetsystems.com/labs/articles/Adobe-Premiere-Pro-CC-2015-3-CPU-Comparison-849/
even AE cc is slower most the time on dual cpus
https://www.pugetsystems.com/labs/articles/Adobe-After-Effects-CC-2015-3-CPU-Comparison-847/

and some nice charts showing the demolishing returns with core count and cpu count
https://www.pugetsystems.com/labs/articles/Adobe-After-Effects-CC-2015-3-Multi-Core-Performance-843/

but yes some apps will scale better with cpu/core count & most normal apps will use 1-3cores max

 

[ActionableMango]

When does Mac Pro use dual CPU? Only if I use specific programs like Premier pro? I recently notice that the 2nd CPU is always hot while the other one is quite cool and I assuming that Mac Pro does not using dual CPU all the time.

The second CPU is hotter than the first because it's behind the first so it's getting cooled by the warmed up air from the first.

You can determine when your Mac Pro is using which CPU by installing software that monitors these things, such as iStat.