How many stems can you play without the disk overloading

[alexfsu]

I composed everything in Reason and have 80 stems--I don't want to group things yet because I want to cut reverb tails and get everything as tight as possible that was in MIDI. But the orange D is lighting up and nothing will play for long without sputtering. I selected RAM on all stems. What else can I do to play all these stems at once? I don't want to bus out stuff in Reason yet if that's possible.

Also I've tried Rewire but that maxes out my CPU, Ableton doesn't know why.

edit: I was running the stems off an external hard drive, I guess that's the reason. Anything I can tweak to be able to run off the drive?

[Tarekith]

Go USB3 if your computer supports it? Or just load the stems you need onto your internal drive while you're working on the project, then copy it back?

[H20nly]

Go USB3 if your computer supports it? Or just load the stems you need onto your internal drive while you're working on the project, then copy it back?

Agreed. Especially on the moving the files to the local disk.