Memory issue running 4 clients on one computer?

[Chorizotarian]

The more clients you have per harddrive the more they will fight over harddrive access. If possible spread them out a bit.

The difference between 1 harddrive hosting 4 clients and each client folder having its own harddrive is huge.

This is probably right if you create 5 copies of WoW via Ctrl-V / Ctrl-C. If you symbolically link them though (Vista mklink, XP linkd) this doesn't seem to happen. I'm running them all off 1 disk, and I don't see any disk contention issues.

If anyone wants to try it out I can provide a PowerShell script that creates a new linked copy of WoW w/ 1 command.