Idk if this is right but my 3750k is hitting mid 70c at 4.2Ghz with just the multiplier adjusted to 42. I have the H60 on the rear port with a second 120mm with 78cfm in push/pull blowing out the rear of the case.
2 120mm intake on front and a 140mm exhaust on the top.
You only pushed the multiplier up? Is the voltage set to automatic? That is quite a bit of heat for only 4.2Ghz. The H60 isn't a "great" cooler but still I don't like the idea of hitting mid 70's at that multiplier.
Question 1 : How are you getting your load temperatures? Games? Prime95? IntelBurnTest? Each will affect the CPU differently temperature wise.
Question 2 : Have you learned about voltages and how to stress the CPU?
Question 3 : Have you done much learning on overclocking with your setup?
A big thing with SB/IB chips is the variable voltage. When you increase the multiplier the voltage seems to up itself pretty good. Heck, with my 2600k on auto voltage the system will draw over 1.3V at a simple 4Ghz overclock. So you might want to learn about voltages and how to read them. Use applications to find out what kind of voltages you're seeing and compare them with BIOS readings and read about your processor. I know a lot of people don't recommend much over 1.3v on an Ivy Bridge like yours; personally from what I have seen the i5-3570k should actually be stable or close to stable at 4.2Ghz@1.2v. Correct me if I'm wrong but that seems about the norm.
You can run different types of voltage but I suggest you learn about the processor you have and read what others have experienced with your chip. Just remember, pushing too much voltage into your chip can fry it and put you back into the CPU purchasing market. So study up about it. If your IB is anything like my SB was when I first tinkered with it; automatic voltage settings sent my CPU into the clouds for heat on a Zalman 9500A.
I figured I better add to this. If you use IntelBurnTest, remember that Linpack/IBT will heat your processor up hotter than anything you'll ever do with it. Prime95 is a good way to get a "max" load temperature. And gaming gives a good variable temperature and usage. So each method is good to know where you stand.
If your temperatures are high, there's a couple things to check and this will be an easy to refer to checklist.
Thermal Interface Material (TIM) or Thermal Paste application
Fans/Airflow through the case
One good thing to always do before overclocking is to get a list of load temperatures on your processor while it's on all stock settings. This will give you a good "base" to go from. But when I started working with the voltages of my CPU, I learned that Automatic pushed over 1.2v into my CPU at stock frequency. However my CPU was 100% stable at 1.175v@4Ghz. So there was much unneeded voltage into my processor. The temperature difference was from 70C to 50C under Prime95 Blend in a 75F room. So my suggestion, learn about voltages and learn about how to overclock the chip you have with the motherboard you have. If you're lucky like me, you'll get to 4.4Ghz or so and have lower temperatures than you did at stock settings.
I have it on auto voltage and I use intel burn test and real temp.
IBT gets me to 72C
Planetside 2 gets me to 55C ( Assassin's Creed 3 doesn't go past 55C either)
I played almost three hours of planetside 2 and about 1h15m of it was a pretty intense large fire fight with medium settings @ 1680x1050. By the way I do know how to overclock. Reason why I only asked about temps with a H60 in push/pull...