I am currently running this system http://outervision.com/b/LrckCX but with a Geforce GT 640. My plan is to replace that with a Geforce GTX 970 for gaming purposes and add an SSD to install a new game on and my OS. Will this be overkill for this machine and should I purchase a GTX 960 or something lower instead? All advice is GREATLY appreciate! Thank you!