I repasted my graphics card less than a year ago, but it is now reaching about 60°C under medium load with a 95°C hotspot. I'm not a particularly heavy user, so that seems unusually soon for the thermal paste to become a problem. Does paste quality make a significant difference, and how often do people normally need to repaste their GPUs? I used Arctic paste from a legitimate retailer, and after opening the card I noticed the paste appeared to have separated and become oily. Further investigation suggested it may have been from a defective or recalled batch of Arctic MX-5.
4 Answers
Some Arctic MX-5 batches were reported to separate, becoming oily instead of staying as a consistent paste. If yours visibly separated after only a few months, a bad batch is a reasonable explanation. Clean it off thoroughly and use a fresh, reputable compound—or a phase-change pad such as PTM7950, which tends to resist pump-out on GPUs. Also inspect the thermal pads before reassembling, since damaged or incorrectly sized pads can prevent proper heatsink contact.
Most systems do not need thermal paste replaced on a schedule. Good paste can remain effective for many years, and you generally only need to replace it when the cooler is removed or temperatures clearly worsen. A desktop CPU may go a decade or more without needing attention. Graphics cards and laptops can be more sensitive because of repeated heat cycles, but even there, one year is unusually short unless something else is wrong.
A 60°C core temperature by itself is fine, but a 95°C hotspot indicates a large temperature difference across the GPU die. Check that the heatsink is making even contact, that all screws were tightened in the correct order, and that the fans and case airflow are working properly. Dust, a changed fan curve, higher ambient temperature, overclocking, or failing cooler hardware can also cause this. If the card is throttling, the hotspot is worth investigating rather than assuming the paste is automatically at fault.
Paste can gradually pump out from the area over the GPU core after many heat cycles, even when the compound itself has not completely dried out. This is more common on high-power graphics cards than on CPUs with a large heat spreader. Repasting every couple of years may be reasonable for a heavily used or older card, but repeatedly doing it every few months usually points to mounting pressure, paste quality, or another cooling problem.
The card was only opened after it began thermal throttling. The paste looked separated and oily, which is why I started suspecting the compound rather than normal aging.