Adding memory certain fix for sluggish PT?

I just got a new 3Ghz P4 machine for PT. It works very well. However, I have one session that uses a bunch of plugins at the same time, including: SampleTank2, Guitar Rig, Waves RVerb, and BFD. I use BFD in Ultra mode, with individual outputs of each drum component (by far the best drum plugin ever made). With all of these loaded, PT crawls to a halt, and I can barely play my recordings, having to go to 512 samples in the Setup mode. My question: Would adding 1GB of RAM from my existing 1GB help at all? Is the performance the processor that is maxed out, or is it memory usage? BFD must be memory hungry, because the pristine samples are larges (200MB for a cymbal hit with decay). One thing that works is to unassign a given plugin when recording, but then I have to reprogram all the I/Os from scratch when I put it back on. With BFD and 20 drum components, it takes 5mn. Is there a way to unassign a plugin but not lose all its settings upon reloading it?

With all those samples loaded into memory, I'd be suprised if it didn't help some, but you could also be reaching the limits of your CPU. What does the CPU meter say? What does the Performance tab in Windows Task Manager (CTRL+ALT+DEL) say about your memory when the session is running? You could try printing some tracks if you're not actively working on them. Say, print the Guitar Rig tracks and free the CPU load while you mess with BFD, then print the BFD tracks to use while you work with Sample Tank... You can always revisit them, but if you're satisfied with the sound there's no reason to keep running the plugin. Print it!

Ditto on printing the Guiter Rig tracks as it is a big cpu hog. I've had sessions go from red to 50% just by printing 3 GR tracks.

I agree w/print effects. You could also increase your H/W Buffer to the maximum if you're done tracking.