What is your camera, make and model?
Also, what is the speed and connection type of that third HDD, the one that I assume that you are Capturing to and then storing the media on?
If you have a red line above your clips, then render the preview by pressing [Enter]. The red line will go green after a while.
What type of HD are you capturing HDV or AVCHD?
PRE will struggle with only 2GB RAM. If your XP is 32-bit you would see improvement upgrading to 4GB. If you have 64-bit then, providing supported by your motherboard, 8GB would be a major boost.
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