Help with decision OCing my i5 3570k

Just watch your temps. You'll get to a point where even your closed loop liquid can't pull the heat away from the CPU. Intel uses a cheap thermal paste under the heat spreader of Ivy Bridge CPU's, instead of solder.
http://www.youtube.com/watch?v=XXs0I5kuoX4

I'd just leave it at 4.4GHz

OK thanks for advice

I would suggest the 4.6Ghz overclock. Every time you add .1Ghz to your overclock your performance goes up by about 3-4%. So .2Ghz will give you 6-8%. And that's a fair amount of extra CPU power. Personally I would go for it.

When I was at 4.5Ghz my temps stayed below 70C in prime95 with an air cooler. So at 4.6Ghz with a water cooler you should still be below 70C as long as it doesn't take too much voltage.

What are you using to stress test your CPU? Intel Burn In Test is the absolute BEST. My Prime95 temps are 10-15C cooler than when using IBT. Also you should use the program "Core Temps" for temps obviously.

Re-test with IBT and Core Temps and then get back with us and let us know what your real temps are. Then you will be able to REALLY tell if your too hot.