Hello! I have Macbook Pro Retina(early 2013) with 2.6Ghz i5 and 8GB RAM. I dedicated Parallels 4GB of RAM, set it to use 2 cores and 512MB of video RAM. Installed host OS is Windows 7 Ultimate x64. Its still somehow laggy even in very basic and old games. What would you suggest? More cores? And maybe a stupid question, but when I quit Parallels, does it immediately rellocate that RAM and processing power back to OSX? Thank you very much!