Often overlooked and taken for granted, thermal paste is a necessary component in PC assembly and while the retail packaging for CPUs typically come with a heatsink and fan with thermal paste applied at the factory it typically isn't the best for ensuring that the maximum amount of heat is transferred from the processor to the heatsink especially if the CPU is going to be overclocked. Thermal paste is designed to take up the gaps between the heatsink and the IHS of the processor, thus eliminating the air in the gaps. Metal to metal contact is best for maximum heat transfer. There are many thermal pastes available, so which one does one choose from? We hope to shed a little light to this confusing topic.

In the past we have talked about the significance of ensuring that components stay within operating conditions to ensure long life and continued functionality.  Let us rehash it a little bit, electronics, in normal operations, generate heat. This heat needs to be moved away from the component and expelled. If the heat is not moved away or is allowed to remain, electromigration can occur. Electromigration is physical damage/wear to the traces cause by electrons moving through them. The more heat that is allowed to build up, the faster the electrons move, causing more damage. While there are numerous heatsink/fan combinations available, often over looked is the thermal interface material that resides between the IHS of the CPU and the base of the heatsink. Metal to metal contact is best for optimum heat transfer, but due to manufacturing and machining processes that may not be possible in many cases. So we have to use a thermal interface material. The main purpose of the thermal interface material is to fill minor gaps that can allow air to get trapped between the IHS of the processor and base of the heatsink, air is a great insulator and allows heat to remain close to the component. 

Today we are taking a look at Noctua's NT-H1 Thermal Interface Material. Noctua has a reputation in the industry for producing very competitive CPU coolers and fans. As the NT-H1 is non-conductive it can be used on GPUs and chipsets as well as CPUs. Maintaining the maximum amount of heat transfer will ensure long life of the components being used.

 Specifications

Features

	Excellent performance NT-H1 consists of a hybrid compound of different micro-particles, which has been specifically optimized for use in PC environments. Thanks to its extremely low thermal resistance as well as excellent pliability and spreadability, NT-H1 achieves outstanding results.
	Maximum ease of use & efficient dosage As NT-H1 spreads very well under pressure, there's no need to smear it over the heat-spreader. This reduces both the consumption of paste and the time spent on the installation process: Put one drop of NT-H1 onto the centre of your CPU, install the cooler and that's it!
	Top-performance right from the start NT-H1 reaches its full performance extremely fast and doesn't require a longer "burn-in" time.
	Excellent long-term stability NT-H1 doesn't contain any solvents or other substances with low flash point and provides excellent long-term stability. Due to the compound's exceptional curing, bleeding, dry-out und thermal cycling characteristics, NT-H1 can be used for several years without any problems.
	Not electrically conductive, non-corroding NT-H1 possesses a very low dielectric constant and a high dielectric strength. Therefore, there's no danger of short-circuits even in case of direct contact with components or conducting paths. Fully compatible with all materials commonly employed in PC environments, NT-H1 is suited for use with aluminium and copper coolers.
	Suitable for compressor cooling NT-H1 is perfectly suited for use with compressor coolers. Even at the very lowest temperatures, the paste delivers full performance and remains easy to clean off.

Packaging

The packaging of the NT-H1 is a very simple affair. The thermal compound comes in a simple cardboard backed blister pack. The back of the packaging contains a wealth of information, such as installation instructions, specifications and one very important warning. The warning states that using too much T.I.M. can cause temperatures to rise and heat to become trapped at the device. Remember that metal to metal contact is best for thermal transfer and any thermal interface material that is needed is used to fill tiny imperfections between the two contact surfaces.

The NT-H1 is contained in a syringe tube and is 1.4ml in weight. Noctua states that this is enough to do 15 applications. During our testing we are going to pit the NT-H1 up against some Artic Silver 5. Now before I get tons of hate mail, I know that AS5 needs curing time where the NT-H1 doesn't, but even with a fully cured AS5 set up you would still only see between a 3-5°C drop, which at this point I do not find as a significant difference.

Let's test it out.

Testing & Conclusion

To install, I used the advice given in Benchmark Reviews' article Best Thermal Paste Application Methods. The article explains that the "Pea Sized drop" isn't necessarily the best method and to apply the T.I.M to our cooler I used three even lines spread evenly on the base of the cooler. This resulted in an even spread of T.I.M across the base. Just remember that thermal interface materials were intended to fill the air gaps produced by machining and using too much can interfere with the results.

Although this isn't the cooler that I used for testing I wanted to see how well the NT-H1 spread, and I can say that it actually spreads fairly easy. I decided to test it on a heat-pipe cooler as there are more gaps to fill. For this picture, I applied a small amount of T.I.M. to the cooler and then spread it with a razor blade, pressing the material into the gaps as I went.

Room Temperature was kept at a constant 25°C and all case fans were set to low. The computer was booted and allowed to idle for 15 minutes. Any fluctuation in temperature resulted in an addition 5 minutes of idle time. Temperatures were monitored using Lavalys Everest Ultimate edition as well as the OCCT temperature monitoring. OCCT and prime 95 ran for an hour and temperatures were recorded at that point. Tests were run three times and the average temperatures were recorded and averaged across the three tests.

Conclusion

Comparing two high end compounds yield similar results with very minor differences and although I did not have any at the time of testing, when you put the NT-H1 up against plain old thermal grease that is when the temperature difference can be seen. When you dive into the world of overclocking, the thermal material choices become even more important, especially at higher overclocks. Overclocking the processor results in more heat being produced at a faster rate, so the better thermal conductivity that you can attain, the better off you are.

Again, this test was performed with no cure time for the AS5 and additional cure time would drop temperature some. The Noctua NT-H1 performed very well at both stock and overclocked settings and was able to keep the processor under that magic 60° C mark that I have set up. The NT-H1 receives our HOT HARDWARE AWARD!

I want to thank our friends over at Noctua for sending out the NT-H1 sample for review.

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