Thermal Grizzly Kryonaut vs. Paste X (pre-series) in the thermal paste test: Changing of the guard after 10 years?

Today I’m testing two pastes from Thermal Grizzly. The Kryonaut, which has been following us for almost 10 years and seems to be stuck between every second CPU and its cooler in the forums, and a new paste as a “secret” pre-production product that will be on the market in around three months. I have already tested this paste internally and today, with Roman’s kind permission, I am allowed to present and compare the product exclusively. And I can spoil one thing in advance – the two pastes are really quite different. That increases the excitement even more.

But let’s stick with the already known product for now. The success of the Kryonauten is probably also due to the fact that even back then they managed to develop a rather liquid paste that nevertheless had a fairly high thermal conductivity. Due to its consistency, it was usually easy to apply and “foolproof” (if we ignore a few batches), which of course also ensured that it always came out on top in the tests (including mine). In practice, a more slippery paste also leads to thinner layers and thus lower thermal resistance.

With exactly this strategy, i.e. as fluid as necessary and as heat-conducting as possible, they have created a real long-running success, without which this company would probably not exist in its current form. But you should always look ahead…

This is where the second paste comes into play. It is relatively viscous, but not quite as solid as the Thermalright TF8 and about on par with the Corsair XTM 70. A paste with a higher filling, i.e. a mixture of soft matrix and significantly more heat-conducting particles, improves performance immensely, but also makes handling a little more complicated. The new paste – I’ll just call it Insert X– is still quite manageable. The product doesn’t have a name yet, but I just couldn’t resist using the grizzly bear prank. Apart from the taste, the color and consistency are similar, but unfortunately the name is already taken. Perhaps you can think of something suitable.

An important preface on “thermal conductivity” and false marketing promises

I’m deliberately putting two quotes before this, which not only speak from my heart, but also absolutely agree with my laboratory measurements. Under the usual conditions on a GPU or CPU, conventional pastes cannot achieve much more than 4 to 5 W/(mK) in terms of layer thickness, temperature and pressure. Because these quotes are honest and unfortunately also correspond to reality, I will now use this part as a standard quote in all paste tests from all manufacturers and put it at the front. You just can’t bend physics.

Anyone wondering how to get values ​​above this limit should know that it is quite possible to adjust the test conditions so that you get astronomically high values. However, testing in a bucket has nothing to do with reality, even if you use a known measurement method. Without knowing the exact circumstances, such values ​​are completely misleading and meaningless. You can give credit to many suppliers for simply not knowing any better and simply copying the OEMs’ data sheets, but misleading consumers doesn’t make things any better.

The previous “reference paste” will only be used for comparisons in the curve diagrams until the automatic, database-based chart generation is ready (soon). Then the best pastes will be used fully automatically for comparison in the charts (can be selected and deselected, just like with the fans). For long-term comparisons, the Alphacool Apex was and is my tool of choice, as I was able to test its behavior over 12 months. With the switch to the database, this point is no longer relevant.

Real long-term simulations (3000 hours in 1000 cycles up to 90°C) are not feasible due to the effort involved. Therefore, I can only make predictions here, but I would like them to be understood as such. It is virtually impossible to make scientifically sound statements in just a few days. Yes, you can identify a trend based on existing data and scale it up as a forecast, but that is not something that really allows for reliable statements. So I regret to say that I have to leave out this important point. However, as time permits, I will take the feedback from the community into account and add the comments and long-term experiences of third parties to the database as a note in due course if it seems necessary. Both in a positive and negative sense. However, this is a subjective value that has no place in a comparison database.

unpacking

In addition to the paste, the Kryonaut also comes with one or two rubber nozzles as applicators, at least in my large family pack. Those in the know like to use glasses cleaning cloths for cleaning, which are significantly cheaper than those offered in computer shops. So the fact that nothing is included here is easy to overlook. 🙂

The new Paste X doesn’t have any packaging yet, I just have a standard screw-top jar for internal use. The paste is still a small series and was therefore produced by Thermal Grizzly in Germany. But it will be a pleasure for me to test the finished mass product later.

Technical data

Let’s leave the marketing aside for a moment and look at the technical data of this paste, which is available in various containers and sizes. We can see that the information on thermal conductivity is missing (red). The green columns contain my measured values, the grey columns contain the completely missing manufacturer information.

Further links and basics