- Created on 02 November 2008
When building a PC, probably the most overlooked component is the Thermal Interface Material (TIM). The reason a TIM is required is due to the relatively irregular surface of the CPU and heat sinks. Although not evident to the human eye, both surfaces if visualised at atomic resolution would look like mountain ranges. Therefore if the surfaces were directly mounted without TIM there would be air gaps between the surfaces that would be poor at conducting heat. The TIM is a low thermal resitance compound (normally silver based) that ensures the optimum transfer of heat away from the CPU to the heat sink of the CPU cooler, by bridging the gap caused by the irregular surfaces.
Most retail packed CPUs come with a stock pad of TIM that melts during use to provide a better transfer of heat, whereas most aftermarket CPU coolers come with a packet of TIM for application to the CPU before attachment. The problem is that these standard TIMs do not tend to be of the highest quality and over time can harden and become brittle (increasing the potential of air gaps) reducing the removal heat from the CPU and therefore increasing the overall thermal load on the system.
With this in mind Noctua have introduced their own TIM: Noctua NT-H1. Noctua NT-H1 comprises a mixture of microparticles that help bridge the gap between CPU and heat cooler similarly to other TIMs. The first difference we ntoiced was the colour and consitency of NT-H1. It is a grey/silver coloured compound which appears to be quite workable, unlike other aftermarket TIMs. This means that application is much simpler, there is no need to spread it over the CPU using a hard surface (such as a credit card or razor blade). Application was simply a case of squeezing a 4mm blob of the compound onto the cleaned CPU and then positioning the CPU cooler with a couple of twists on top of the CPU to spread the thermal compound out evenly (see the manual here).
Our test rig was a Intel Q9450 CPU, Abit IP35 mainboard, Nexus PHT-7750 SkiveTek Radial CPU cooler installed in an Antec 1200 case. The Noctua NT-H1 compound was directly compared against the Artic Silver 5 TIM compound that we previously had "installed" using OCCT to monitor and induce stress conditions (100% CPU usage for 1hr). Interestingly we saw no difference between the two compounds, both gave idle temperatures of 29C and stress temperatures of 52C. This is a good result for the NT-NH1, as the Arctic Silver 5 compound is widely recognised as one of the best TIMs available.
Beyond the actual thermal properties, the NT-H1 does not require a burn-in time, unlike the Artic Silver that requires a two week period before it is at it's full potential. Also it boasts an excellent long-term stability, with reapplication not required for several years. It is not electrically conductive so there is no chance of short circuits if applied incorrectly, and is non-corroding and therefore compatible with both aluminium and copper coolers. NT-H1 is also compatible with compressor coolers that work at significantly lower temperatures than air coolers and water cooling systems, with an optimum working temperature range of -50C to 110C.
We found the NT-H1 easy to apply and it provided similar results to Artic Silver 5. With the host of other benefits that this TIM boasts, it should definitely be considered when building a new PC or upgrading an older one. To put it into perspective, we are still using it on our test rig!