Why my PC not using all cores on My Multicore Games? (Getting bottlenecked)

TwinDenis

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Hi, so I am noticing, if it is indeed true, that in multicore games my PC uses one core almost maxed and the other cores little bit used usually.
I was told by the game companies that their games were multicore while this effect was happening.
So it is a bottleneck of some sort the result of this, fps drops not gpu-wise but when smoke, fog, particles etc. So basically when cpu is needed. Which is needed a lot in some games so I tend to constantly micro-stutter in some cases.
I have this posted again but this thread focuses on the specific of CPU 1 core usage instead of the intended multicore.
You can check my other post here:
https://linustechtips.com/main/topic/540311-why-is-my-pc-bottlenecking-in-games/?page=1
There you can find useful information of the situation and plenty of graphs and screenshots.

,Thanks.
 
Solution
This is normal. Most game processing is serial, and really can't be broken up into smaller threads. Most games can do 90% of their work on just two or three threads, which limits how much additional cores help performance. That's why strong cores are preferred to more cores in gaming, and why Intel's i5 lineup is preferred in gaming builds, since there's little extra benefit to purchasing an i7.

Textbook case of Amdahl's Law, really:

https://en.wikipedia.org/wiki/Amdahl%27s_law
This is normal. Most game processing is serial, and really can't be broken up into smaller threads. Most games can do 90% of their work on just two or three threads, which limits how much additional cores help performance. That's why strong cores are preferred to more cores in gaming, and why Intel's i5 lineup is preferred in gaming builds, since there's little extra benefit to purchasing an i7.

Textbook case of Amdahl's Law, really:

https://en.wikipedia.org/wiki/Amdahl%27s_law
 
Solution

TwinDenis

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what if I have a xeon e5-1620 and having these kinds of issues?
More or less an i5 is of lower speed. So if an i5 is good for games then my cpu should be better as well. Not to mention not doing these kinds of bottlenecks. Or rather choppy fps when cpu aspects load.
 
Without knowing the SW in question that's doing this, it's hard to comment farther. Most games don't really scale beyond two cores, because most of the work can't be made parallel. Most i5's should be able to handle pretty much anything out there though.
 

TwinDenis

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This could help determine whats going on, this is on Blade and soul.
Similar to other, lower demanding games, the same effect happens.

Bn_Stestbenchmark2.png

could it be ram bottleneck? (4x2gb ecc 1333mhz.)