64GB is plenty for a RAM disk — just don’t allocate all of it.

Yes, 64GB is enough to see a real benefit for a RAM disk, but you’ve got to leave enough RAM for Photoshop and your OS.

Photoshop uses scratch when it runs out of available RAM. A RAM disk turning that scratch into lightning-fast memory is great on paper, but if you slice off too much of your 64GB, you’ll actually make Photoshop work harder because it has less room to breathe.

I’d allocate 16–24GB for the RAM disk, leaving 40–48GB for the system and Photoshop. That’s more than enough for most workflows. If you’re editing massive 50-layer files, sure, bump it up, but 64GB total is already generous.

It’s not overkill — you’re just giving scratch its own express lane. Just don’t cut off your nose to spite your face.