I installed my 3080ti two days ago. It seems to work great! The first day I installed it, I ran a test:
8K Premiere Pro 4 minute sequence with 8K video (I know 8k is ridiculous overkill)
Lumetri color effeft added
On my old 1080ti, this took over 3 hours. Once I got the 3080ti up and running it went down to about 26 minutes, which was awesome! However, ever since then, Premiere Pro and AME seem to refuse to use the GPU for rendering at all. For this 8k test, or for 4K or regular HD content. Render times are extremely long, and GPU usage is minimal in Task Manager. I've made sure everything is set to Hardware Encoding/CUDA rendering.
Every once in a while, without changing a single setting, it'll actually use the GPU, and the render time will be a fraction of the former CPU bound time. What's going on? What can I do to improve render times? I've got a fair amount of content to churn out for a client, and as it is, my PC will need to be rendering overnight, and that seems absurd with this new 3080ti installed.
It's your CPU. Seriously. Far too many people configure gaming PCs with monster GPUs but underpowered or weakling CPUs. And video editing PCs work best when the relative performances of both the CPU and the GPU are closely matched. That i7-7700K has only 4 cores and 8 threads - outdated by current mainstream standards, when even mainstream CPUs have 6 or 8 cores and up to 16 threads. Plus, Kaby Lake's IPC is somewhat lower than current mainstream standards.
This is one instance where you have a GPU that's quite overqualified for your CPU. You have wasted money for this GPU upgrade, in this particular case.
While I do plan on upgrading my CPU to Alder Lake when it comes out later this year, I'm pretty convinced that that's not the situation here. Two points here: One is that one the first day the GPU was installed, AME *flew* through sequences an order of magnitude faster than it did previously with the old 1080ti--26ish minutes in my test case versus 3 hours with the 1080ti. Using those same exact sequences and same export settings two days later, AME (or Premiere Pro) both state that it will take right at 6 hours--slower than my previous times with the 1080ti.
Second, during this time, the GPU is barely being utilized which seems to indicate that's shifting the encoding over the CPU. Regardless if the CPU was new or old, I'd expect the GPU usage to be completely maxed out. The GPU just isn't being used, regardless of CPU power.
On both the new and old GPU, I've seen it fly through renders when Hardware Encoding is used. It's awesome!! It just seems like now 95% of the time, AME just shifts everything over to the CPU. Every once in a great while, I'll send a project over and it'll clearly use the GPU, and the encode will be lighting quick. I just don't know what's causing it to not work that 95% of the time.