You'll need a new motherboard. The i3-3225 is an LGA 1155. The i5 4690k (Devils Canyon) is on the newer LGA 1150. They are not compatible, so you'd need a new motherboard. While yes, the above poster is right if you want for pure performance buying a new gpu is the way to go. BUT I'm fearful you'll be doing nothing BUT creating an even bigger bottleneck. Will it still run? Well, yes. You'll still see probably a 30-50% increase in fps. So I mean, possibly buy the gpu now, see if it gives you the boost you want/need for the moment. And in the future buy a the new cpu/mobo when price comes down. Guy above is right though, the new cpu will show little improvement fps in games. To say it makes "no difference" isn't really accurate though that depends entirely on the games you play. You can see through benchmarks the difference in games like BF4, Dragon Age Inquisition etc. the difference between an i3 and i5 are 5-10 fps sometimes.