computer overload on effects? UA?

I use both proTools LE and Sonar 4 Producer.. First off, Sonar is much easier to use and far more intuitive.. Why isn't it more accepted as compared to proTools LE..?

However, although I have a pretty powerful built computer, it seems to get hosed out and overloaded whenever I use a few poweful processing tools. I have UA's vintage card and it's supposed to run well because it's its own power source.. Still I get overloaded and it won't hold.. Suggestions?
I have P4 1gigDDR ram and it should be okay, no?

Your best bet is to record your effects.. especially on cpu intensive stuff like reverbs and echoes.
For instance, set your reverb so that you just hear the 'wet' sound, then export that to a stereo audio file. Now turn off your reverb and fade in the 'wet' sound on the other track.

The problem could be the ram... I use 2GB and have no issues with multiple VST's and plug-ins. I use an M-Audio Delta 1010 and find it great. It has 10 1/4 inch in's and 10 1/4 inch out's, very handy for recording. Only problem is no XLR's (if that's what you're looking for)... It takes all of the load off the CPU so you get zero latency. Another thing worth checking out is the processor speed and chip set in your current pc. If you have an older motherboard running all the latest powerful hardware its like putting a Mini engine into a Porche, it won't have the power to drive the rest of the hardware. A lot of software now is released with the recommended spec above what is available on the market at the time (eg GigaStudio) so the product lasts longer for the developers. If you check out tech support for the software your running and ask them what they would recommend for the optimum performance you may be surprised that it varies significantly to what you thought.