Hi; Upon overclocking only 2-3 hundred Mhz, my CPU overheats up to 65C at least.  I purchased this after market cooler: http://www.tigerdirect.com/applications/searchtools/item-details.asp?EdpNo=4974358&pagenumber=1&RSort=1&csid=ITD&recordsPerPage=5&body=REVIEWS#CustomerReviewsBlock.  What gives?What CPU?

I can't find any information on the TDP of that heatsink but it doesn't look like it would do much better than a stock cooler.AMD FX-6300 3.5 Ghz CPU.  The cooler was $25.  I have a mini-ATX mobo.  Do the heavier duty coolers fit a mini-ATX mobo/tower?I had a fan that was sucking the wrong direction.Hi; I have a micro-ATX mobo and my CPU is an AMD FX-6300 3.5Ghz processor.   I'm looking to buy a cooler for this build in which I can achieve a substantial overclock.  Is it feasible?  I just want a fan/heatsink cooler.  I'm not looking to GO water-cooled.  My CPU is a 95W.  My PSU is 650W.   Upon attempting to overclock, Prime95 quickly raises the CPU temperature up past 65C on a mere raise of 200Mhz.  Can you suggest a good cooler?  I'm prepared to spend at least $60-85.What CPU? You said AMD FX-6300 3.5Ghz.
Most modern CPU designs allow the chip to get close to 90 C and not crash.
THEE is no simple way to extrapolate  a relation with clock, power and temperature. Other that to just says temp goes  up when the other FACTORS go up.

In other r words, a 20% up clock does not mean a 20% temp up.

The CPU may stop before you get to its temp limit. Thee is another reason for the clock speed limit other than  temp.
Here is a link that may be relevant:
http://www.pcworld.com/article/198882/overclocking_for_newbies.html
But that was written some time ago.