Random frame rate drops on the desktop


Junior Member
Aug 15, 2019
I've had a problem with now two different (AMD) cards and I'm hoping someone here has any ideas of what's causing it or knows a fix.

Occasionally, seemingly randomly, when I use my PC the frame rate of the entire system just drops to a very low level and everything becomes choppy/laggy, easy to notice when scrolling a webpage, for example.
When that happens I can go to this site and see that the frame rate is around 16 fps. (With the other card I believe it was around 30.)
But as soon as I move any program window the frame rate returns to normal, aka 75fps/Hz in my case.
The monitor itself stays at 75Hz, at least that's what it says in the monitor menu. It also says 75Hz in the Windows monitor settings.

Currently I use a Radeon 5450 and before that I used a 7850. I tried different driver versions and also the drivers provided through Windows Update. It doesn't make a difference. This problem happens about once every 3 hours of PC use (very rough estimate).

I found a thread with a couple of guys posting about the same issue here, but no solution.

OS is Windows 7 64bit. It's a pretty clean PC without much nonsense installed. I do use f.lux, which I thought could be the cause, but I tried turning it off and it didn't help (unless I'd also have to restart after?).


Diamond Member
Dec 10, 2010
What CPU do you have?

I have not used f.lux, but it sounds like it skews the color warmth via software, not via any monitor controls. I would uninstall it completely and see how things go. It may not be the cause, but its worth trying.

When this issue happens, try running Task Manager on the Performance tab, and select GPU on the left. Just see how things look on the graphs.


Golden Member
Sep 16, 2009
Are you sure it's from the graphics cards and not something else? For example faulty storage that forces an immense load of interrupts requests, thus the system delays?

Check your SMART status on your storage.


Junior Member
Aug 15, 2019
Thanks for the suggestions. I've already checked the GPU readings with Process Explorer and there's nothing unusual. The SMART readings are fine too.

I'm not 100% sure it's the graphics cards themselves, but I'm almost certain it's something related to graphics and the way Windows handles it.
I don't see any other explanation for the things returning to normal as soon as I move a window. It seems like something related to DWM/acceleration...

At this point my main suspect is f.lux, maybe in combination with a 75Hz monitor. I already know f.lux can cause weird problems in other areas.
Yesterday I've uninstalled it, rebooted and ran for almost the entire day without the bug ever happening. I'm now trying an older version (3.12) to see if it's any better.


Junior Member
Aug 15, 2019
Update: looks like f.lux is not the cause either. I uninstalled it completely and still got the bug after a few days.
A next potential suspect is WizMouse...


Senior member
Nov 30, 2016
An easy way to determine if the problem is software related is to boot the machine up in safe mode and see if the issue persists.