Re: Upgrading parts
It's not worth to upgrade your current E6300 for an E6600. Just overclock it past the E6600 speed, and it will perform better than the E6600.
With the graphic card, that is like night and day right there. Worth it. Make sure your power supply is sufficient enough to handle the 8800GTX.
Well for the hard drive upgrade, I think you should get another 250GB, and RAID with your current 250GB. You get even more space, for less money, than getting another 10k rpm drive. And it will perform equal to that of a single 10k rpm drive.
3770K | ASUS STRIX GTX 1080 | DDR3-1600 16GB | CORSAIR 650D | CORSAIR HX 850W | CORSAIR H100 | SOUND BLASTER Z | ASROCK EXTREME4 GEN3