I recently upgraded from a hard drive to a brand new SSD, 1 terabyte. I think it's an 840 evo or something, I'm kinda forgetful. Was like night and day difference. Now, my hard drive might've been a slower version, but my SSD was top on the market. Costs me about 460, but it was money WELL worth it after I loaded it up. Lag was MUCH less and my computer was already upgraded in every other way, this just let it reach the limits it had. Every game I have now runs at lightning speed, hard drives can really hold you back with some stuff. Any lag I have now is all software related and optimizations.