I've switched to MSI Afterburner. Aorus engine, as it turns out, not only has the least responsive user interface since last time I used a windows XP machine, it also does not even work.
With MSI Afterburner I was able to turn down the memory clock by 502MHz, which could have fixed the random freezing if it was due to bad VRAM. This did not solve the problem however.
I've also tried turning down the memory clock together with underclocking the card so that its boost clock is equal to the normal base clock, but this also didn't help.
I have contacted NVidia's customer support just in case it is a graphics card problem after all, but since underclocking the card did not fix anything I highly doubt it is a graphics card stability issue. If this leads to anything useful I'll be sure to post it here as well. NVidia customer support did not turn out very useful, and reiterated that this is likely a issue with the game rather than the graphics card.
This once again makes me believe this problem is in fact a bug in the game. To summarize the symptoms are:
- Freezes up to one second, usually in the 100ms to 300ms range.
- High usage on one CPU core at the time of the freeze, low usage on the rest. Usually all cores are at 60% utilisation.
- Low graphics card load at the time of the freeze. It drops to about 50% whereas this is usually 94%. This and CPU usage characteristics where measured while running in windowed mode.
- Freezes seem to coincide with certain in-game events.
- The graph enabled through the PerfOverlay.DrawGraph command reveals a spike in CPU time equal to the length of the freeze, GPU time always remains stable an within reasonable bounds.