Will I see any performance increase?

Like others have said LLMs mostly use VRAM, they can use system RAM if you’re running them on CPU, but that’s ridiculously slow.

It will however increase the speed of your compile times, which is especially useful if you’re compiling something large like the Linux kernel on a regular basis.

I’m also worried about not having ECC RAM.

If you are using it purely for LLMs, if it’s going to get bit flips, it’ll happen in VRAM.

If you are compiling large things for customers, I’d recommend ECC, just in case, e.g. you don’t want a bricking firmware from a bit flip. But according to EDAC and my TIG stack, my server’s ECC RAM has never even detected an error in the past year, if I understand EDAC properly, so it’s really not important.