Hello all!
COOLER QUESTION:
I'm new here at the forums and have a question regarding compatibility for a CPU cooler. Due to some issues with my E6600 Core 2 Duo's stock cooler I've decided I'd like to upgrade the fan/heatsink for it. After some minor searching on newegg, I noticed the Arctic Cooling Freezer 7 Pro was the appropriate socket and extremely popular/highly rated. However, I was concerned about the possibility of it not fitting on my motherboard. I have an ASUS P5NSLI motherboard on my computer, at least for now, and was wondering if anyone was familiar as to whether or not the Freezer 7 Pro properly mounts on the board without any interference with the nearby heatsink or other components. I checked the dimensions and it seems like it might be close but I'm not certain that I'm interpreting the dimensions properly and wanted to confirm one way or the other. And if the cooler doesn't fit (or if nobody knows), is anyone familiar with another good fan & heatsink that definately does fit.

And finally, what sort of temperatures should I expect at idle/stress with a mid-range cooler like the arctic cooler pro? I don't intend to do any overclocking but am just curious as I made a rather serious mistake with my current setup's temperatures that could have possibly already damaged my CPU and I don't want to do that again.

OVERHEATING QUESTION: I'd also like to perhaps get some other opinions on whether or not overheating is definitely the source of my problem.
The Actual symptoms I have been encountering are as follows: Recently my computer has been seemingly randomly shutting off, usually during some sort of usage. At first I thought it might the the PSU, but then after a bit of research some other things made me think overheating. First, if I tried to start up my comp after it shut off, it would shut off a few seconds later again unless I waited for a while (I waited at least 10 mins). I removed my computer from it's desk compartment, which was almost certainly bad for cooling in the first place. The frequency of the computer shutting of declined significantly, but not entirely. As such, I checked vid card and cpu temps, found the vid card to be fine, but I'm pretty sure the cpu is too high.
Like I mentioned above, I'm currently using an Intel Core 2 Duo E6600, at its standard speeds. I found that I was idling it 60C in BIOS, and when running core temp in Windows, (still not stressing it with anything other than basic always-running background processes and a web browser) the temps rose above 70C...under any type of stress I assume it would go above the 85C barrier. (60C was listed as running hot for my processor especially for idling, and 85C was the max junction temp listed in the guide AND in core temp) I figured that the computer was shutting of as a mechanism to prevent the cpu from frying itself. Any thoughts as to whether or not this is
the case?

Thanks much ahead of time

Your stock Intel CPU cooler is almost certainly not-quite-properly mounted. Due to the poor Intel cooler mounting design, this is sadly very common. Your idling temps (assuming decent case airflow) should be no higher than 5-10C above ambient (so 25-30C for 20C ambient (room) temp). The mounting instructions in this post may prove helpful: http://www.tomshardware.com/forum/ [...] y#t1184072
The key tips are:
1) Mount the cooler only with the MB outside the case; when the MB is already mounted in the case, there's often too little room between the back of the MB and the case wall for the pins to get fully through. It's also very difficult to visually confirm that the pins are fully through.
2) Before pushing each pin, make sure it is turned completely *opposite* the direction of the arrow on top. The arrows are for *removing* the cooler.
3) Push the pins in an "X" pattern: push one, then the pin diagonally opposite it, then the last 2.

Finally, if you do decide to go with an aftermarket CPU cooler, remember that the stock Intel cooler has a secondary cooling function: cooling nearby components such as the northbridge and PWM area by blowing air down and out over the motherboard in all directions. Most aftermarket coolers, like the Freezer 7 Pro, don't perform this function, and your MB looks to be especially sensitive to its lack, with the heatsinks on the northbridge and PWM area lacking any heatpipes or fans.