Theoretically, the maximum amount of RAM your computer allows would be the ideal amount. You can never have too much, and it only helps improve things.
Legacy Forum Post
about 18 years ago
The recommended minimum is 512mb to run Virtual Drumline (along with the sampler program and notation program simultaneously). If you are attempting to run more samples on top of that, you may be OK with 512mb, but if you are attempting to access a lot more samples on top of that the more RAM you have, the better.
If you're running into polyphony problems, or CPU usage is maxing out, one workaround (in a pinch) would be to run your pit or band sounds from your computer's soundcard. If you're really getting "the bug" with stacking a lot of sounds, most "power users" will use a separate computer as a "slave" while writing the music/notation on their main computer. Check page 10 of the VDrumline help file for an illustration of how such a system might be setup.