You don't list your graphics card, which is about the single most important piece of hardware you can use to speed up a system for gaming. Based on your current hardware setup, if you installed a current cutting edge graphics card, it would gain you far more overall performance than any other upgrade possibly could.
RAID 0 often gives a slight increase in speed, but it is usually only slight and most users cannot visibly tell the difference between a RAID 0 and a single disk system under normal use.
If you were manipulating some vast video files, for example, you will probably notice a benefitial speed increase from a RAID system. Gaming is not comparable along these lines though. It is a systems ability to continuously update and refresh the video display that calls up some pretty hefty graphics performance for games.
I'd say a current leading edge graphics card would offer you far more performance than any form of RAID ever could for gaming. While RAID may pep thigs up a little bit, a good video card will take you to completely new heights. That, after all, is a video cards specific job in life.
Finally, it is far simpler for all of us if you continue on with your original thread rather than starting a new one that follows on from the same subject. Some people get a little confused over which one to respond to, so in future could I ask that you either mark your original thread as resolved so that nobody tried to post to it or just add on to it until you have reached a satisfactory conclusion ?
Thanks for that.