ALPHACOOL has finally settled on carrying two brands namely APEX and CORE each with different ideologies and products. Seems like they will broadly be using these two series in the coming future. We have received APEX Thermal Paste for testing. Thermal paste is of paramount consideration when it comes to the effective cooling of the main components like CPU, GPU, PCH, and any other chipset. There are multiple factors contributing towards the optimal performance of the given thermal paste over the period of time like its thermal conductance, viscosity, operating temperature range, make-up, electrically conductive, cure time, etc. The thermal conductivity of this paste is rated at 17 W/mK. It is an electrically non-conductive and high-pressure thermal compound with a viscosity of 1,500,000 to 2,000,0000 mPa.s depending on the temperature. We will compare this paste against the Noctua NT-H1. While this thermal paste seems to have a bit better thermal conductivity rating, it is nowhere near the viscosity of Subzero thermal paste.
It is important to pay attention to the packing quantity of the thermal paste when comparing the price. Alphacool has sent us a 20gm pack which is listed at €59.98. However, this thermal paste is also available in other-size packs. The Noctua NT-H1 is available in a minimum of 3.5gm pack and a maximum of 10gm.
|Thermal Paste||Quantity||Price||Price per gm|
The price of Noctua NT-H1 is taken from the NewEgg and the prices of APEX various packs are taken from Alphacool Online Shop. We can clearly see that up to a 4gm pack of APEX thermal paste is costing more than a 3.5gm pack of Noctua NT-H1. But remember, pricing is only relevant and we need to put the thermal performance into the equation to make a full picture. Please keep in mind that Euro and US dollars are trading at 1 Euro = 1.07 USD at the time of writing this content.
Let’s start by looking at what Alphacool is saying about this thermal paste. “The Alphacool Apex Thermal Grease is intended for all users who want to achieve the optimum performance with their system. With a thermal conductivity of 17 W/mK, this electrically non-conductive thermal paste suitable for high contact pressures is clearly the favorite when performance and ease of application are required. Alphacool’s Apex Thermal Grease has an extremely high thermal conductivity of 17 W/mK, making it one of the best performing thermal pastes on the market. Only liquid metal thermal pastes offer better thermal conductivity. The Apex Thermal Grease is delivered in a 20g container with screw cap. The amount of thermal paste is sufficient for several applications and can be stored in the container protected from drying out. In addition, Apex Thermal Grease is non-conductive and non-caustic. If a small amount of paste is spilled during application, damage to the hardware is highly unlikely.”
The thermal paste is shipped inside a container without any packing box. It has APEX Thermal Grease written on it.
A serial number label can be seen in the above picture. Article number is also printed.
The capacity of this pack is 20g and this thermal paste is made in France. Finally, we have seen a non-Chinese or Taiwanese manufacturing.
The color of this thermal paste is gray.
The above picture is showing the specifications of this thermal paste. This is a Silicone based thermal paste with fillers. We were able to find the data on the mixture (fillers) listed in their safety data.
- Zinc Oxide 10-30%
- Aluminum Powder 55-85%
- Liquid Polymer 10-30%
The initial boiling point for this thermal paste is >200°C whereas the melting point is not determined. Density is mentioned as 3.48g/cm³ and it is mentioned as 3.2 g/cc. The good thing about this thermal paste is its viscosity. Due to its relatively high viscosity, this paste is expected not to bleed or disappear quickly. This viscosity rating sits between the Thermal Grizzly Kryonaut Extreme and ALPHACOOL Subzero thermal paste. According to ALPHACOOL this paste is non-conductive and non-caustic.
Now coming to the main point of this article, the following configuration is used for thermal paste testing: –
- Intel i7 10700k [5.0GHz at 1.350V]
- MSI Z490 TOMAHAWK
- Noctua NH-D15 Chromax.Black
- T-Force NightHawk RGB DDR4 16GB @ 3200MHz CAS 16
- Colorful iGame GeForce GTX 1050Ti [For Display]
- Addlink S70 256GB NVMe SSD [For OS]
- bequiet! Straight Power 11 850W Platinum PSU
- Praxis Wetbench
Following testing methodology is used for the thermal paste testing:
- Intel core i7 10700k was set to run at 5.0GHz on all cores using 1.350V.
- The chip was drawing power of nearly 182W on the package.
- A graphics card with a much higher heat load or the HEDT/EPYC CPUs with large surface areas is a better candidate for thermal paste testing.
- Thermal pastes were spread evenly on the CPU IHS.
- A test run of 30 minutes was done using Cinebench R23.2 on stock settings first.
- PC was powered off for a minimum of 30 minutes after a stress test run. This would allow the completion of the thermal cycle with hot and cold runs giving the thermal paste some time to reach its near-optimal condition.
- The system was put on idle for 10 minutes before taking the Idle temperature values.
- A stress run of 30 minutes was done using Cinebench R23.2.
- CPU Package Temperature is taken as a reporting value.
- Ideally, we would have wanted to do 3 tests as a minimum for a single thermal paste and show the average of these three runs. I am recovering from a total hip replacement surgery and slowly resuming the testing hence only one test result is used
- The fans of the air cooler were set to run at their full speed for which the settings were made in UEFI/BIOS.
- HWInfo64 was used to monitor the sensors.
The above picture shows a thermal paste placed over CPU IHS before spreading evenly.
Please note that not every run of the stress test may yield the same result. This could well be due to many factors like mounting pressure, thermal paste application, and varying ambient temperature. Not to mention the silicon differences even among the same category of chips. Hence, it is pertinent to mention the testing methodology along with the specifics. Each time the even spread of the thermal paste was verified and where the thermal paste spread was not even or gives the impression of a tear or a poor application, the result was dropped and the new test with the correct spread was repeated. This is done to ensure the validity of the data.
In case you are wondering why I did not use a new platform like AMD Ryzen 7000 series or Intel 13th generation platform, the issue with new platforms is their high thermal density. AMD Ryzen 7000 series CPU will hit 95°C which is by design whereas the Intel SKUs run warm even on stock settings. This makes it difficult to test the coolers and thermal pastes the old traditional way. The only way around is to see for how long a given cooler can maintain the operating frequencies before hitting the thermal junction or what score a cooler gives in software like CINEBENCH R23.2. Cutting it short, we stick with the 10th generation platform so that we can test using the traditional way.
Let’s take a look at the results.
Thermal Grizzly Kryonaut Extreme lowers the temperature by 2°C over the Noctua NT-H1.
Alphacool APEX is a high-performance thermal paste suitable for users who would want optimal performance from their systems. This thermal paste is available in multiple-size packs including:
- 1gm Pack
- 4gm Pack
- 20gm Pack
- 50gm Pack
- 100gm Pack
Alphacool has sent the 20gm pack for testing. According to Alphacool, this thermal paste is:
- Electrically Non-Conductive
- High Pressure
- High Viscosity
- High Thermal Conductivity
This thermal paste has a thermal conductivity rating of 17W/mK making it among the few listed options in the market to touch this high rating. This is further augmented using a high viscosity rating of 1,500,000 to 2,000,000 mPa.s. These two variables make this thermal paste a good candidate for high-pressure mounting. Particularly, with this viscosity, we would expect this thermal paste to last longer without bleeding or disappearing. Alphacool did not mention the cure timing but it seems like it has minimal to no cure time. The paste has a gray color and its specific gravity is 3.48 g/cm³. The operating temperature range is -40~120°C. The maximum working pressure rating is 40 PSI.
The application of the thermal paste is convenient. You can use the spatula to evenly spread the paste or simply use a blob method for even spreading coming from the mounting pressure. ALPHACOOL has suggested using the spread method for optimal performance but they do not provide a spatula with this thermal paste. One thing we have picked from their statements (mentioned on website) is that spilling a small amount of this thermal paste is highly unlikely to damage the hardware. This is a confusing statement given that this thermal paste is electrically non-conductive. Same statement is mentioned on Subzro thermal paste’s webpage.
The pricing of the thermal paste is €59.98 at the time of this writing. Calculating the 1gm price would give us a €2.99 price tag. Converting this into equivalent USD, we get 3.21 USD. This is more expensive than a 3.5gm pack of Noctua NT-H1. But we can see that buying more capacity packs would actually give a better value. Why? Simply because this thermal paste in our thermal testing is giving up to 2°C better performance over Noctua NT-H1. Alphacool is giving 2-year warranty on this thermal paste. We have compared the Alphacool Apex with the Noctua NT-H1. In our thermal testing, there is a difference of roughly 2°C favoring the APEX thermal paste albeit at a bit high price tag.