If you're idling at 40C or higher; you've either got the voltage pumping to that chip something fierce or the thermal conductivity from the CPU to the HSF is bad (thermal paste)
First thing to do is go into the BIOS and look under the hardware monitor and come back and tell us what the voltage is. If it's over 1.25v there's a serious problem and it's time to really reset the bios and get that voltage down as at load it may be spiking enough to pop that chip and that makes for an expensive little silicon based paperweight.
Second, if the voltages are normal, you need to reapply the thermal paste! MOST IMPORTANTLY, clean the CPU and the HSF off with isopropyl alcohol 70% or higher and apply it correctly...
Methodology of applying thermal paste...
Step 1 : Clean the CPU and HSF with isopropyl alcohol
Step 2 : Put a small dab onto CPU
Step 3 : Press HSF onto CPU and twist about 20* each way while applying pressure.
Step 4 : Remove HSF from CPU and check for proper coverage/spill over. The idea is to get as much of that CPU covered as possible without it going over. If you don't have at LEAST 90%-95% of that CPU covered with thermal paste or there is a lot that ran off the side of the CPU, go to Step 1 and repeat the process. If you got a good spread with little or no waste over the side and a very good spread with maybe only a smidgen of the corners untouched, then go to Step 5. Anything else than that, go back to Step 1.
Step 5 : Clean the CPU and HSF with isopropyl alcohol. Repeat the method that achieved excellent coverage. DO NOT PULL THE HSF OFF OF THE CPU. If you know you had a good application and you repeated the steps properly, do NOT remove the HSF. You need to keep the HSF on the CPU without moving it other than slight rotations and bolt/fasten the HSF down.
Step 6 : Awesome Temperatures? If no, Step 1 again.
It's a process just like a programmer would make. Trial and error until you find the exact amount for your HSF/CPU/TIM combination. What I use with MX-2 and MX-4 is about 3/4 of what I had to use with Artic Silver 5. So each TIM is different.
Try this out and then let's see those temperatures.
Explanation for the fast 30C to 100C temperature change... The CPU itself will heat up in a matter of seconds. It's left to the HSF to draw that heat out of the CPU as fast as it can. That's where the TIM comes into play. If you just touch metal to metal, you have to hope for heats version of osmosis to take place which the CPU would fry before it actually managed to draw the heat. The thermal paste on the other hand can increase this draw by an exponential amount. The biggest thing here is if there's too little, it can't work properly. If there's too much it can actually act as an insulation. The object of the TIM is to make the HSF and CPU basically become one giant chunk of metal which allows the transfer of heat from the CPU to HSF instantaneously. However, it's not a perfect science and cheap TIM won't perform as good as something like IC Diamond. But without it, it's almost as bad as running with no HSF at all.
I hope this helps out!
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