Noctua NT-H1 Pro Grade Thermal Compound Specifications

From Noctua’s web site:

Noctua’s NT-H1 is a pro-grade TIM solution for enthusiasts who demand both exceptional performance and maximum ease of use: A hybrid compound of different micro-particles allows for minimum thermal resistance, excellent ease of use and outstanding long term stability.

Here are some of the ‘Noctua NT-H1 Pro-Grade Thermal Compound’ product descriptions:

• Excellent performance
• Maximum ease of use & efficient dosage
• Excellent long-term stability(recommended up to three years of usage)
• Not electrically conductive
• Non-corroding
• Suitable for compressor cooling
• Thermal Resistance: Not disclosed by Noctua
• Dielectric Constant@ 1KHz: 4.0
• Dielectric Strength: 1.5 kV/mm
• Specific Gravity: 2.49g / cm3
• Thermal Conductivity: Not disclosed by Noctua
• Poise: 4800
• Color: Dark Gray
• Volume: 1.4ml syringe
• Peak Operating Temperature: -50C to +110C
• Recommended Operating Temperature: -40C to +90C

How Thermal Compound Works

Let’s explain first what TIM (Thermal Interface Material) really is. Thermal Interface Material is a substance designed to take heat from one object and transfer it to another. It could be silicon based, metal based or ceramic based. We’ll use all three different ones today in our tests. It is mostly used in the computer industry for dissipation of heat through a heatsink. CPU’s and GPU’s generate tons of heat and we all know that heat is bad for our computers. So we want the product that is going to help us most in keeping our rigs cool. The workings of TIM are based on a difficult formula that looks like this:


Hold onto your hats folks, this is where it gets complicated.

Thermal conductivity = heat flow rate × distance / (area × temperature difference). In physics, thermal conductivity, "k" is the property of a material that indicates its ability to conduct heat. It is defined as the quantity of heat, "ΔQ", transmitted during time "Δt" through a thickness "L", in a direction normal to a surface of area "A", due to a temperature difference "ΔT", under steady state conditions and when the heat transfer is dependent only on the temperature gradient. (Thanks to Wikipedia.)

Well, that is not the only difficult part. When we're talking TIM, we also have to look at the density, viscosity, thermal resistance and now that Noctua claims that NT-H1 is non-conductive, we also have to look at a new term: Dielectric Constant. Our product has a density/gravity of 2.49 g/cm3 which is explained like this: Density is mass (m) per unit volume (V). To keep it short, Noctua NT-H1 is 2.49 times denser than water. Which is better for the thermal conductivity and thermal resistance. See how it all comes together? Viscosity is explained like this: the measure of the resistance of a fluid to being deformed by either shear stress or extensional stress. In other words: the thickness of a fluid. It is measured in cP (Poise). With Corn syrup being at 1300cP you can now imagine what the Noctua NT-H1 looks like. As for dielectric constant numbers, the lower its value, the less relative static permittivity is has. In Laymen’s terms: It is non-conductive.

Now, let us take the CPU/Heatsink combination for example. These two surfaces are never really flat, meaning that if you put the heatsink on the CPU, there will be AIR in between the two of them. And that is BAD. Air is 8000 times less efficient in conducting heat than your thermal paste. What the thermal paste does is basically fills up the minute gaps, scratches and dents in between the two, so that heat can dissipate faster.