Why does my cpu bottlenecks my GPU???

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Rcr1094

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Dec 26, 2014
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Hello people.. My pc specs are here;

Amd fx 8350
Sapphire R9 290x Tri-x
ddr 3 1600 mhz
MSI 990 FXA GD65

My problem is that I never see my GPU usage at %100 and I get lower FPS than I should.. My gpu usage is fluctuating between 0-100 constantly, it is really really unstable.. But when I downclock my GPU on MSI afterburner, GPU load hits %100.. I tried to overclock my cpu to 4.4 or 4.5 but my pc shuts itself in short time.. BTW I have a gigantic cpu cooler that barely fits in my pc case.. Here's the solutions I've tried so far;

- Changing my GPU with another one by warranty..
- Uninstalling the gpu drivers by DDU and re-install them
- Installing the latest driver & bios to my MOBO
- Installing the latest GPU drivers
- Re-Installing my OS
- Overclocking my cpu; changes a bit but not much.. GPU load is still unstable, fluctuating between 0-100 constantly.

I searched the internet for a while and found out that many people had issued with these 2 (r9 290x and FX 8350) but I also saw people with no problem with them. and many people can hit %100 GPU usage with these 2??.. I do not know what is wrong and I am running out of options.. After changing my GPU with new one by warranty, I started to think that problem is my cpu.. What do you guys suggest? Thanks.

 


welll his gpu is actually old.. I have already another gpu's for myself such as gtx 470 and hd 7850... I do not run into these issues with them.. only when I install my 290X, does this start to happen..
 


I dont actually know :/ All I know it is 650W psu... I dont even know if it is 80 plus
 
Personally I'd put a good PSU such as a Seasonic 750-850 watt in for more than one reason. The AMD mobo chipset will also limit performance of a R9 290X, I have a few of them and they do far better in Intel 4790K & Z87/Z97 platforms.
 
Look into programs from iobit. Advanced System Care 8 did wonders for my pc that was already 100%. And my Dads eMachine from 2004 that took 5 minutes just to get to the internets home page. Trust me look into it, they give you 3 pc keys to share with anyone. And the prgrams are at such a low price its amazing. TRUST ME, it can't hurt. Goodluck :) :bounce:
 


It sounds like you work for them? This is not something that will be resolved by adding random unrelated software.
 


I agree.

 


I tried a different pc.. I actually tried many many things last night but most of them did not work since my friend's pc is kinda old... What I was able to achieve that I put my graphic card and PSU on his system (since his psu did not run my GPU :/ ). He has a first generation i5 processor and low ram (2gb) .. and result were same.. fluctuating gpu usage....... so I was wrong to blame my CPU maybe.. Rest of the stuff I tried did not work..

This test left me 2 choices... Either my psu is not good or my GPU (2nd same gpu actually since I already returned one and got this one in return) is somehow broken...

 


Since i saw your 3d mark scores i told you that is something wrong with your gpu or the power that the gpu receives.
 


yes, now we are sure of it.. but I have another problem now.. since I put my parts back to my case my system would not start??When I push the power button, lights are up fans start to turn, but the system keeps restarting itself .. nothing comes up the screen.. I think I plugged something wrong. I will try to fix it tonight..

It sucks to have a problem.. Because it raises another problem on the way to fix it :)
 


but psu was working fine on the other system?? When I plugged everything back, something went wrong and system would not open..
 


Fluctuating issue is visible on every game actually, no matter which hardware it requires... I think the gpu usage should be like stable 40-50 if there is a bottleneck.. But my issue is different because I see 0 as well.. It is never stable...
Here is a video I took with my previous R9 290X that I returned.. Watch the GPU usage please.. You will see what I mean.. This is not an ordinary bottleneck imo..

https://www.youtube.com/watch?v=sURJMLgZlyQ&feature=youtu.be
 


Yes it does the same on MSI afterburner as well :) FPS is lower than it should but no freezing even if it hits 0 or low usage like 10-20...
 


Sure I will.. I will fix my pc tonight and start downloading Tomb Raider..
 


I think I wrecked my mobo 😀 😀 No matter how hard I tried, I am unable to start the system... It just keeps restarting itself even if I take off the GPU and Ram and everything else except cpu and psu... I am sure it is not PSU because it was working on the another system.. and cpu was ok before these processes... Now I will have to get new mobo.. And I am sure it will not be AMD again!
 


Watched your YouTube video and I seen absolutely no bottleneck happening. Lets say your game uses 2 threads. If there was a bottleneck those two cores would be maxed out. When maxed out your gpu usage would drop because the cpu can't keep up. I didn't see that at all. I think that's the software giving wrong values. As for the no post I would get your PSU tested to see if it's fried before replacing your board and cpu. I have to agree with the others that suggest your PSU is toast. Bring it to a local computer store and have them test it. If you should need a new one make sure it's made by Seasonic as they are the best. I have a rule of thumb when buying a PSU. If the system takes 500 watts to run I buy a 1000 watt PSU. Why the over kill? That's because the PSU runs at it's best efficiency at 50% usage. Plus you will get a few builds from one power supply.