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Question

Possible Bottlenecking Issue among other issues

Apr 10, 2015 8:50AM PDT

Here is what I'm running:

Unigine Heaven Benchmark 4.0

System
Platform: Windows 7 (build 7601, Service Pack 1) 64bit
CPU model: Intel(R) Core(TM) i7-4790K CPU @ 4.00GHz (3997MHz) x4
GPU model: NVIDIA GeForce GTX 780 9.18.13.4752 (3072MB) x1

FPS: 55.5
Score: 1397
Min FPS: 29.9
Max FPS: 116.9

Settings
Render: Direct3D11
Mode: 1920x1080 8xAA full screen
Preset: Custom
Quality: Ultra
Tessellation: Extreme

I have reason to believe that my CPU is bottlenecking my GPU.

The evidence that leads me to believe this is when running prime95 alongside Unigine Heaven 4.0, I see extremely low quality benchmarks. We are talking about 10 FPS low quality.
When I turn off prime95, I see more acceptable benchmarks of 50+ FPS with some spots reaching 100+ FPS.

From what I have read, this means that my CPU is bottlenecking my GPU.

Is there a way to fix this issue?

I have read that a fix would be to overclock the CPU. I believe there is already an overclock on it. Not sure if it is a factory boost setting or if Ironside computers put it on there. It's rated at 4.0 GHz but according to HWMonitor I'm running pretty close to 4.4 GHz.

Also, to compound this issue; while running Prime95 alone, my CPU temps reach 100C on multiple cores. It doesn't stay there, It reaches it in around 30 minutes then goes back down to the 70's, then over the next 15 minutes or so it slowly climbs back up to 100C again then slowly goes back down to the 70's again. This repetition continues during the entire time Prime95 is running.

It only does this while Prime95 is running; my temps don't go over 60C while doing anything else. So I am hesitant to try overclocking it more than it already is for this reason.

The fix for this would be liquid cooling. I already have a stage 2 Iron Tundra liquid cooling system (I'm assuming this is something that is named by Ironside). It has a very large radiator at the top of the case along with very thick transparent tubing for the liquid. The reservoir is full as well. On top of that there are 4 different case fans. The case itself is a Cooler Master HAF X. It is in a well-ventilated area. Not sure what I could do to get it cooler.

Another thing that may be worth mentioning (not sure if it is related or not) is that every time I turn my computer on and log onto WoW, both screens go dark for a few seconds and I get an error saying that my NVIDIA display driver has temporarily stopped working but has recovered. It only does this one time during my whole session. It does not do this again until I shut the computer down and start it back up again. I have read about a few possible fixes for it, I have tried rerolling back to a previous video card update, running MemTest to see if it's my ram, and set the NVidia settings to prefer performance instead of energy saving. None of this has fixed this issue.

Does anyone have any advice that would help me out with these issues? I consider myself to be a novice when it comes with anything to do with computers. Everything that I have written is essentially the boundary of my computer knowledge.

Thank you!

Discussion is locked

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Answer
Doubt it's the CPU.
Apr 10, 2015 9:01AM PDT

My thought is its the usual like 8xAA.

Here's why I doubt the CPU.
"Our tests demonstrate fairly little difference between a $225 LGA 1155 Core i5-2500K and a $1000 LGA 2011 Core i7-3960X, even when three-way graphics card configurations are involved. It turns out that memory bandwidth and PCIe throughput don't hold back the performance of existing Sandy Bridge-based machines. "
http://www.tomshardware.com/reviews/gaming-cpu-review-overclock,3106-4.html

As to your proof of Prime95, no gamer I know would soak the CPU during games or testing.

The other usual is "Quality: Ultra". For now we have to get into the 970/980 class cards to run consistent 60FPS rates. To get great rates you only need to pull back on the settings a little.
Bob

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Do you have any other opinions on my other issues?
Apr 10, 2015 9:12AM PDT

So I get that reducing the AA down from 8x would make a difference and I will definitely try that. Do you have any opinions on my other issues, such as 100C being temporarily reached while running P95? Or the temporary failure and recovery of my NVIDIA driver every time I start up WoW?

Thank you

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Prime95 should engage all cores to near 100%
Apr 10, 2015 9:18AM PDT

So running that along side a GPU test could drop the load. Still an interesting idea or test. I won't put much work into guessing why your gear got that hot. Could be case temp, heatsink compound issues or other.

The failure of the Nvidia driver is all over the map on the web from a stressed PSU, Bad Caps to other. It's so much over the map that unless I have the machine in front of me I don't dive into that.

Take a view with GPUz and read what was found at http://www.tomshardware.com/answers/id-2008606/gtx-780-memory.html

It looks like that card was bunked.
Bob