Modern graphics cards use a lot of power, all of which turns into heat. Therefore, if one is paying hundreds of dollars for a powerful GPU, one would expect no expense to be spared on the cooling system. However, in the case of many Nvidia RTX 40 series vendors, no expense was spared and cheap, poorly made thermal paste was found to be causing hot spots to become hotter and performance to degrade over time

. [Hardware tester Igor's Lab tested multiple GeForce RTX cards, analyzed temperatures and performance, and found that the thermal paste used by many graphics card vendors was not only unsuitable for this task, but also poorly applied

My office has been working on this project for several years.

I have four RTX 40 series cards in my office (RTX 4080 Super, 4070 Ti, and two 4070s), and they all have fairly high hot spots (the highest temperature recorded by the individual thermal sensors in the die); in the case of the 4080 Super, about 11°C above the average chip temperature higher than the average temperature of the chip. When we took them apart to apply a decent quality thermal paste, we found a similar situation to that found by Igor's Lab.

Over a period of several months, the factory-applied paste had separated and spread, leaving behind an oily film and only a little of the thermal compound itself. I checked other cards and they were all in the same condition.

Igor's Lab examined the thermal paste used on the new RTX 4080 and found that it was quite thin, due to the large amount of cheap silicone oil used along with the zinc oxide filler. There was a lot of ground aluminum oxide (the material that provides the actual thermal conduction), but it was quite coarse, making the paste very easy to separate.

By removing the factory paste from another RTX 4080 graphics card, Igor's Lab found that applying a more appropriate amount of high-quality paste reduced the hot spot temperature by nearly 30°C.

But hotspots are not the only problem: GPUs slow down their clock speeds as they reach their thermal limits, so using cheap, inferior thermal paste can degrade graphics card performance over time. PC enthusiasts will have no qualms about replacing the thermal paste on their CPUs on a regular basis, but for graphics cards, it is not an easy task.

If you've spent $1,000 or more on a graphics card, it stands to reason that this work shouldn't be necessary for years.

In my case, changing the paste on the RTX 4080 Super did not improve the hotspot delta (I will eventually try the PTM7950), but the overall die temperature dropped several degrees. I am monitoring all four cards regularly to see if the temperatures start to rise, but I also feel that I don't really need to do this. [While Nvidia enjoys huge margins on GPUs, graphics card vendors are not so lucky, but spending a few dollars more on better thermal paste is not small enough to bankrupt a company.

If all GPU vendors started using the PTM7950, this would not be an issue. The only problem is that with the reduced fan noise, you will hear the whine of the coils.

Yeah, PC gaming is never easy.