Hey I agree with everything Walter said. However, one factor that could be interesting to test is how much the speed of your ram would affect preview performance. I don’t think it would make a huge difference but I really don’t know and haven’t come across any benchmarks for vfx work. I just thought of this because I recently bought new ram and I had to manually set it to it’s advertised speed to get the full benefit.
You can change your Ram Clock speed in your bios menu. A fair amount of motherboards default your speed to like 2133mhz. If you paid the premium for the 3400mhz you should check to see if it’s running properly. There have been benchmarks showing that in RAM intensive games, clock speed can make a considerable difference in performance, (10-20%). After effects is certainly ram heavy so it might have similar benefits.
It’s kind of complicated to change, but checking it is easy enough. When your computer is booting go to the bios menu usually pressing f2 or delete and you will have to navigate the menus to a tab that says something like overclocking or performance. There you can check your cpu clock speed and it should have info about your ram as well. Don’t change anything without researching it first. These instructions will vary based on the parts in the computer so sorry they’re a little vague. I don’t think it will make a huge difference but I’d be interested in your results if you do test it!