32-bit apps use more memory in a 64-bit OS vs a 32-bit OS. That's because everytime a 32-bit program requests 32-bits to store a info, the OS gives it a 64-bit block. Given your memory usage though I wouldn't think that was it, but adding memory couldn't hurt ^_^. If you're using a 2GB DIMM and a 1GB DIMM though your memory will be running in single channel and there is a performance penalty with that. Anyway it likely sounds like a driver problem, probably with the webcam driver.