Can PSU bottleneck performance?

gamingwoop · Jun 1, 2015

My 630W PSU should in theory easily accommodate my R9 290x.
I've noticed I'm not quite getting FPS that others are getting with similar builds (but not too bothered), so wondered if in fact it could be the PSU, and how would I test it?

I've tested CPU and it's not that..drivers are up-to-date..

sizzling · Jun 1, 2015

Usually a PSU being underpowered would lead to random crashes or reboots although I guess it might be possible.

Joseph DeGarmo · Jun 1, 2015

It could be that an underpowered PSU will cause the GPU to throttle clock speeds to meet the power limits of the PSU.

gamingwoop · Jun 1, 2015

sizzling :

I havent experienced any of that

gamingwoop · Jun 1, 2015

Joseph DeGarmo :

Do you think thats likely? How could I test it?

DeathRabit · Jun 1, 2015

Run Furrmark http://www.ozone3d.net/benchmarks/fur/ and control GPU temps and Usage , if GPU usage drop bellow 99% you have throttling
To monitor GPU you can use GPU-Z http://www.techpowerup.com/gpuz/

Rookie_MIB · Jun 1, 2015

I don't think it would be possible to limit the performance due to a weaker PSU. If the PSU is being overdrawn, it would be overheating and/or reseting (ie:rebooting, crashes, etc).

If you had a kill-a-watt meter (I have one, very handy and not expensive at all) you could see what the actual pull at the wall is with the meter, and see if you're overloading it. You don't spec the rest of your system, but in general, using the least efficient setup:

130w AMD CPU
290w average R9-290x
50w MOBO
50w drives/fans

530w total. You have about 100w of headroom, which while not the best (150-200w would put you in the efficiency sweet spot), it is more than enough assuming that you're not overclocked. If you are overclocking, then my rough numbers aren't going to be close because power use goes up exponentially (as does heat).

So - I agree that it's unlikely that you're underpowered and the PSU is causing the problems. How about just your regular system design? What -can- cause FPS slowdowns is the GPU getting too warm and throttling. Check your airflow design and make sure that you're not having the fans work against each other.

An easy way to test THAT is simple: Take all the sides off your case, aim a fan at your system, and run the benchmarks. If it goes faster, you have a heat/throttling problem.

gamingwoop · Jun 1, 2015

Rookie_MIB :

Sorry I should've included my full build, here it is:
PCPartPicker part list / Price breakdown by merchant

CPU: Intel Core i5-4460 3.2GHz Quad-Core Processor ($176.98 @ NCIX US)
CPU Cooler: Arctic Cooling Freezer 7 Pro Rev.2 45.0 CFM Fluid Dynamic Bearing CPU Cooler ($19.98 @ OutletPC)
Motherboard: Asus B85M-G Micro ATX LGA1150 Motherboard ($89.79 @ OutletPC)
Memory: Patriot Signature 8GB (1 x 8GB) DDR3-1600 Memory ($52.99 @ B&H)
Storage: OCZ ARC 100 240GB 2.5" Solid State Drive ($79.99 @ Newegg)
Video Card: XFX Radeon R9 290X 4GB Black Edition Double Dissipation Video Card ($352.98 @ Newegg)
Case: Zalman Z11 Plus HF1 ATX Mid Tower Case ($75.98 @ Newegg)
Power Supply: Thermaltake Berlin 630W 80+ Certified ATX Power Supply
Total: $848.69
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2015-06-01 09:16 EDT-0400

PCPartsPicker estimates it at 470W.
One of my fans isn't active due to MOBO limitations, and I will fix that as soon as I can, but despite this my GPU temps never go above 80C at full load...

gamingwoop · Jun 1, 2015

DeathRabit :

So do I check my "GPU Load" during the burn-in test?? Because I did that and it jumped to 4% and 26% and 92% a couple of times randomly (but stayed at 100% predominantly)......or is it another measurement I check?

Search

Can PSU bottleneck performance?

gamingwoop

Honorable

sizzling

Titan

Joseph DeGarmo

Honorable

gamingwoop

Honorable

gamingwoop

Honorable

DeathRabit

Splendid

Rookie_MIB

Distinguished

gamingwoop

Honorable

gamingwoop

Honorable

TRENDING THREADS

Latest posts

Moderators online

Share this page