R9 280x low GPU usage

[Rockcat]

Hi!

So i got new card and new setup, but the problem is low GPU usage in games.
For example in AC 4: Black Flag and Arma 3 GPU usage is only 30-47% and vRAM below 1GB. And there are FPS drops.
But in Natural selection i got maximum of 80% GPU usage and 100FPS.

CPU: AMD FX-8320
GPU: MSI R9 280x
MOBO: Asus M5A97 R2.0
4GB DDR3

 

[laviniuc]

some games are better optimized for multi core cpu-s compared to others. try to get the latest drivers too just in case

 

[hypergon]

It could be your ram bottlenecking, 4gb could be just not enough for 280x. GPU usage should be higher unless you manually lock its performance to a certain framerate

 

[Rockcat]

All drivers are up to date, except BIOS version.

 

[Rockcat]

Thanks for your responses, i will try out extra 4GB ram next week.

 

[photonboy]

I do agree you should get another 4GB of IDENTICAL memory though I'm not certain you should be bottlenecked quite that much.

Going below TWO sticks of 1600MHz does tend to start bottlenecking the average game though the second stick MAY (varies) only help by about 15% or so. Still, it's significant and factor in the poor FX performance in a game like AC4 and your good graphics card might very well be waiting on the CPU a lot.

More:

1) How exactly are you confirming GPU usage?

2) How are your scores roughly comparing to online benchmarks?
(If possible find the same CPU and GPU or similar).

AC4:
GPU benchmarks (with good Intel CPU): http://www.hardwarepal.com/assassins-creed-4-black-flag-benchmark-cpu-gpu/5/

GPU RAM usage: http://www.hardwarepal.com/assassins-creed-4-black-flag-benchmark-cpu-gpu/7/

CPU scaling: http://www.hardwarepal.com/assassins-creed-4-black-flag-benchmark-cpu-gpu/8/

*So as you can see, in AC4 the AMD processors are quite weak. This is because the game can't utilize much more than two cores (despite recommending four). Don't confuse seeing all cores being used, that's just multiple threads spread over all eight cores but the game essentially can't use much more than two full cores as the main processes can't split between more than two.

So if the CPU is bottlenecking things that means the GRAPHICS CARD isn't getting data as quickly so it's going to sit around waiting.

The CPU reads from the DDR3 memory, does some processing itself and forwards instructions to the graphics card. If the DDR3 memory is too slow the CPU is left waiting; if the CPU is too slow the graphics card is left waiting.

In reality it's a little more complicated than all this.

VRAM usage:
Windows desktop can easily use 300MB. It will keep that in Video memory even when running a game unless you go past a certain point (say 80%) of VRAM usage then it's copied to System RAM until the game is closed/tabbed.

Just be aware it can be difficult to compare what other people say about VRAM usage. The correct way is to note the desktop usage before starting the game, then SUBTRACT this from the total used IN GAME, provided usage isn't over 80% (I don't know the actual threshold). This is also how the Pagefile for Windows works except it's from System RAM to the HDD/SSD drive and this is from Video RAM to the DDR3 System RAM.

 

[Rockcat]

1) MSI afterburner + Rivatuner. Also my CPU is near 30% usage, i get what you are saying, that some games dont use more than 2 cores, but the thing is other people with same CPU and GPU OR even with weaker can run this game normally. It is quite hard for me to explain that lag, because my English is not that good. It's not like continuous lag, i can play and then bam, FPS drops terribly for few seconds.

2) I have not used any benchmarking software yet, but i will look for something.

Thank you for you answer and explaining things for me. I will try extra 4GB ram next week and will let you know did it change anything.