I recently upgraded my system HDD to an SSD with a new install of OSX 10.6.4 and mimicked the settings I had on my previous set up to replicate it. however, when for example I was using iTunes to play music the screen saver would come on and a short time later the system would pause iTunes and goes into Sleep mode. my previous install never did that so I'm not sure if its because of the SSD and it not being mechanical it doesnt recognize it accessing or seeking 'per se' because regardless of unchecking "Put hard disks to sleep when possible" it still does it. here is an image of energy saver settings; btw I had the system plugged into and still went into sleep mode when iTunes was playing and even other media formats such as Video in iTunes or VLC. any tips and advice would be greatly appreciated!