So, I have my E8300 running at 4Ghz stable. Ambient room temp is between 75-80 degrees Fahrenheit. The temp question: it idles (0%) at 47C (49C when the front door is shut and it's tilted to block light while I'm sleeping). 100% Load it hits 60C (62C under other stated conditions). Is this too hot, all things considered. Also, my board is an EVGA 680i, cooler is a Coolermaster Geminii with 2 120mm Thermaltake Thunderblades on it, I use OCZ Ultra +5 (same as AS5), and I'm 100% sure it is properly mounted.
i have that same board, but use a Q6600 my general rule is not to exceed 50C under load or around that 60C is hot but wont kill the CPU right away it is decreaseing its life quite a bit though, if i where you i would consider if you really need 4Ghz im sure 3.4 would be fine for what you need and the CPU would last a lot longer
If you going to be overclocking, you really should read this guide. There are two different temperature sensors on your chip. One is the tcase (cpu temperature) which is what auscanzukus is talking about, the other is tjunction (core temperatures). When asking for help with your temperatures, you need to tell us which sensor your reading from, and what program your using. Anyway, reading this guide is recommended.
I'm using core temp and I have a core 2 quad q9300 with box fan and thermal pad that runs 48C idle and 63C 100% load. My last cpu is AMD 64 X2 4800+ and it runs 28C idle 38C 100% load with box fan and arctic silver. I used and ASUS utility to monitor the AMD also. 63C with the Intel was a bit disconcerting. I looked up the Intel documentation and it says those temps are within the threshold. I plan on getting an aftermarket cpu fan and use some arctic silver because if even if those temps are normal that hot cpu is running up my case temp.