Igor, in his latest, has shown that the GDDR6X memory on the NVIDIA RTX 3080 reaches temps as high as 104 degrees. The card tested was a vanilla Founders’ Edition from NVIDIA. As you can see in the below image, the VRAM and memory temperatures on the surface are lower at 90 and 84 degrees, respectively, but when Igor checked the Tj max temperature of the memory module (the hottest region) which is located right above the memory die, he saw temps as high as 104 degrees.
For GDDR6X, the maximum value of Tj max is set at 110 degrees, with 120 degrees being the mark where it can get damage itself. Considering that, this is dangerously close to that value. Luckily, these chips come with an internal protection mechanism that automatically throttles the memory clock if it gets too hot. At the same time though, traditional monitoring tools don’t show the Tj max value of the memory modules, but the ones measured from the PCB, instead. As you may have heard, Micron’s memory is rated at 20-21Gbps, and the reason why NVIDIA has limited it to 19Gbps on its FE cards is because of the thermals.
Igor’s experiments with exotic cooling such a water block and use of backplate showed interesting results. Using a thermal pad on the memory modules reduces the Tboard (reported by PCB and software) by around 4 degrees while also reducing the Tj temp by a couple of degrees. Therefore, with the RTX 30 series take the temperatures reported by Afterbuner or Precision X1 with a grain of salt as the actual temps are much higher. It’ll be interesting to see if custom waterblock makers such as Ekwb come up with any particular solutions to deal with this issue.