There is really no reason to use a SSD for a cache when the OS is on a SSD. The SRT from Intel was designed more for conventional hdd's and they would benefit greatly from a ssd cache. The cache drive can be up to 64gb and anything over 30gb would be a waste of space as the SRT was designed for a 20gb SSD. I would put only put the OS on the smaller SSD and your games and frequently used apps on the larger SSD. I have a similar setup with my OS on a Corsair 180gb SSD and my games and apps on an OCZ RevoDrive 240gb.