GTX 770 sudden FPS drop

[schmoul]

Hello everyone,
I usually manage to find answers to every computer related problem that I previously had, but this one is kind of weird.

It began suddenly yesterday. Now, whenever i'm playing for about 15 minutes, my FPS count halves, no matter which game I am playing. It never goes back to normal again, unless I restart. When I reboot, I can play for 15 minutes and FPS drop again. It is not a temperature problem, I ran some tests with furmark and GPU temp does not go higher than 77 degrees celsius. My CPU temperature seems to be fine too.

With OCCT, I managed to capture the moment when the FPS drop occurs but I don't really know how to interpret this. http://imgur.com/a/HAvQr#1

It seems that my GPU suddenly shuts down, and the CPU begins to kick in.
I also updated my GPU bios and did a clean installation of the drivers, to no avail. Did a virus and a malewarebyte scan and nothing's wrong.

Here's my computer specs :

Intel i5 2500k @stock
Msi GTX770 Twin Frozr @stock
8 gb RAM
Asrock Z68 pro 3m
PSU is a 500w rebranded seasonic

Do you have any idea of what it could be ? Thank you in advance !

 

[Daemmon]

That OCCT pics lack some info, like %GPU usage (or maybe I'm not seeing it?)

It looks like a classic driver crash, weird is, it's not telling you anything about it.

Check event viewer for warnings from display? Maybe there is something hidden in there.

 

[schmoul]

Thanks for your answer ! I know what you mean, I had the driver crash problem with my previous GPU (GTX 560 Ti). It seems different here, as absolutely nothing tells me something is wrong like you said. No matter what I do, the FPS just drop until I reboot, without any other sign. Would a stress test with another tool help ?

 

[Daemmon]

Leave GPU-Z logging while playing/stressing so we can see how the GPU behaves pre/after this. Then attach the logs

 

[schmoul]

I tried yesterday to do a simple system restore from a restore point a couple days before the issue showed up, and I think it worked. I really don't know what program caused this though, because I didn't install anything special in that period of time. Is it possible that a windows update did this ?

Anyway, thanks for your help !