The only one that probably could comment on that much memory might be Eric Bowen.
How do I summon him for answers?
There would be no benefit of having 512GB of RAM for Premiere Pro.
I have 128GB and Premiere Pro doesn't ever use even half of it. Having some extra RAM (over what you allocate for Premiere Pro use) for Windows caching does help performance a bit. Unless you will be using After Effects or some other application that really needs 256GB why not just spec out your build for 128GB (and choose with memory sticks that allow for expansion if you ever decide that you do not have enough).
If anyone tells you that having a RAMDISK is fast, you can ignore that too for Premiere Pro. SSD RAID arrays are faster and way less expensive.
Well, what's the usual size of stuff you export? It's really when exporting out of media encoder that I've run out of memory on 64gb machines, both mac os and windows. I literally have to quit everything else, and even then it sometimes doesn't work. But I often deal with projects that are effectively 10k or so, which is probably not the norm for most people. What I'm really just trying to find out, on a technical level, is when does premier actually use more ram, and under what circumstances would there ever be more ram called for.
*edited for spelling
10k, wow, I've not rendered any of that before! I've exported some pretty small projects with 6k and 8k RD3 media and much longer (60 minute) 4k Sony projects.
Thoughts and / or things to consider:
- I don't know much about it, but I seem to recall reading somewhere that Adobe Premiere CC had a memory leak that was fixed in one or the more recent versions
- I rarely use Media Encoder; I should probably give it a try now, but a couple of years ago (~1st gen. CC), Premiere Pro renders were WAY faster from Premiere Pro for my workflows than using Media Encoder.
- Your projects sound huge and probably too large to send over the internet, but if you wanted to mail me a USB stick with a sample 10k project with media (I'm in the USA), then I would not mind trying it on some pretty decent hardware and letting you know where I see the Premiere Pro bottlenecks. If you're interested, PM me for my email and physical address.