System Spec: CPU: Intel P4 3.8GHz single core | Heat sink type: Block aluminium
BEFORE using MX4: 58-59 degrees C at idle -> C 70-71 degrees C with CPU running at 100%
AFTER using MX4: Exactly the Same. Zero improvement.
I took considerable care cleaning and rubbing down the contact surfaces before applying MX-4. I have not waited for the product to "cure" before reviewing it because it clearly says no curing required.
My conclusion is that a thermal compounds is only as good as the sink it's conducting heat to. If the sink can't dissipate the heat fast enough, you will not see much improvement. Therefore I would NOT recommend this product to anyone with a stock aluminium heat sink. You're better off saving your money and using the grease that came with your sink or any similar cheap product.
I think people who have noted improvements after applying this product must have COPPER or other heatpipe design sinks that can use the extra conductivity of this paste. Or else, they have cooler running CPUs. I don't know. I think some of the more spectacular claims made here are down to improper benchmarking with maybe a little exaggeration thrown in.
Having said all that, I don't regret giving this product a try because now I know for sure that there's no £5 cooling solution for *MY* system. Unfortunately, it cost me £5 to find that out! :>