You might want to go into your settings and set it just to GPU it will add speed to your renders you should have plenty of memory on a 3080 to handle pretty much any render that you do it would have to be a highly detailed scene to use more memory than what that GPU has and I believe you will find out that your renders will speed up significantly if you get it away from the CPU. Just as a for instance those last two renders that I posted ran about 22 to 23 minutes each they're both in 4k but I let them run their course to about 3,500 to 5,000 iterations and I didn't have to go anywhere near that for it to be finished.