When I play recent 3D games (Battlefield 3 & 4, Tomb Raider, Saints Row 3 & 4, etc.) I experience periodic FPS drops, e.g. in Battlefield 3 from the average of around 70-80 fps to 20-30 fps; Even if I stand still and look at the same spot. It happens about every 3s and the drop is only a spike - half a second long.
It's not the graphics card or driver, because I switched my AMD card with an NVIDIA and the problem persists. And while the game is running, I monitored CPUs, RAM, Pagefile and Graphics card: Each CPU core stays below ~70%, no single core goes up to maximum, RAM always stays below 12GB and pagefile doesn't get touched
Now how can I make the fps become constant or how do I debug this issue? I'm out of ideas.
- Motherboard: AsRock Fatal1ty 990FX Killer
- CPU: AMD FX-9370 (4.4Ghz 8-core)
- RAM: Corsair 16GB 1860MHz (2 x 8GB in dual channel)
- PSU: Corsair 750W
- Storage: Samsung Evo SSD (OS) and Samsung 1TB 7200rpm (games)
- Graphics: Asus Radeon R9 280X
What I tried:
- update graphics card driver (to 14.9)
- downgrade graphics card driver (to 13.11)
- switch graphics card to NVIDIA Geforce GTX 760 - still, same frequent fps drops
- play with almost every BIOS/UEFI setting
- reset BIOS/UEFI settings to default
- stress-test the CPU and RAM with Prime95... no power drops, no visual cues that would fit into the 3s-0.5s pattern
- monitor the heat of CPU and graphics - CPU gives me 68 degree Celsius under pressure and graphics don't really heat up too much (sorry, forgot the number). Also the CPU is liquid-cooled.
...here are some graphics: http://imgur.com/a/w0z1o
- Screenshot from Catzilla benchmark, displaying the drops (because it measures and displays the fps constantly, not only every second). I also noted that the frequency can vary a little bit, i.e. the distance between the gaps is not uniform.
- Another Catzilla screenshot, same thing, but only 2s between gaps.
- Screenshot of GPUtweak (a graphics monitoring tool with a time resolution of 1s)... notice that in the first benchmark (left) that causes the lags, there is mixed GPU usage, while on the right in a permanently high GPU test there are none.
- CPU usage screenshot. During the benchmark this spiky pattern occurs - don't know if that's normal or related to the lag issues.
...I also noted that it gets worse after some gaming / warming up. Usually if I run the (Catzilla) benchmark twice in a row, the first run gets 1-3 gaps, while the second run is gapping 10-20 times.
EDIT 1 - 2014-10-05 14:29 GMT+1
I ran the file logging tool of GPU-Z. During the last Catzilla benchmark (during which a large number of spikes occured) there are "power downs" in the column "VDDC Current (A)", i.e. the values look like this:
61 60.2 68 1 60.8
The temporal resolution is 0.1s, so each line is a tenth of a second. Is this normal - maybe during a black screen or something? Also the values in this column highly oscillate over the course of about 2-3s. Maybe a power thing? But what would I check to confirm this - switch out the motherboard or the PSU?
EDIT 2 - 2014-10-05 23:07 GMT+1
...Okay, this is weird. When the system is cold (first benchmark run after a long pause), the lagging disappears, but after getting warm (second benchmark run in rapid succession), the lagging starts and the overall performance drops. When cold the graphics card sensor gives me 40 degr. C, the CPU 64 degr. C. The CPU doesn't change so much (goes up to about 70 under full stress), but when the GPU reaches 65-70 degr. C, the problems occur. But then again... I switched the graphics cards with an NVIDIA - and also I suppose that those are still temperatures that they can handle. Maybe it's the motherboard warming up or something? Is that a thing? Northbridge?
EDIT 3 - 2014-10-05 23:27 GMT+1
In Process Explorer I got a clear picture of the error (right side): http://i.imgur.com/lto29Bb.png