SSD and Memory question

I have my bootcamp partition set up through parallels and it works fine. The only problem is that every bit of the ram I set for parallels is cached on the hard drive, taking about 4GB of space until parallels shuts down. being that I have 8 GB of ram actually installed of which 2 GB is in use, how do I keep parallels from imaging the memory to the hard drive? I have no need for that to be done. I'm assuming that is there in case I want to put windows into hibernation, but I don't anyhow.