How to fix my graphene heatsink

[Bill_Bright]

without providing any ''cool'' air for the radiator from outside.

That is a bit misleading (in part, due to me not explaining myself completely). Since there is some air flow in the case, for sure the temperature of the air inside the case will (should) only be slightly heated compared to the ambient (room) temperature. This means even warm air from inside the case being blown through the radiator will still extract heat from the radiator fins to keep the CPU properly cooled.

Note the radiator of a car in Phoenix in July when it is 115°F (46.1°C) out still keeps the coolant and thus engine adequately cooled. In fact, 2 feet above the asphalt road surfaces can easily reach 150°F or higher and the radiators still work as long as air is flowing through it.

But again, I was referring to the cooling needs of other components, not the CPU.

Here's an intuitive explanation: the glue can't withstand the cold, and it cracks. I don't know if it's correct but seems more likely if the glue is hard, not elastic.

No, sorry - again my bad for not thoroughly explaining myself. I totally understand about "some" glues becoming "brittle" in extreme cold.

I was referring specifically about "epoxy" adhesives, many of which are fully capable of maintaining strength and effectiveness in super extreme cold (-50°F or colder) temperatures, as seen here.

HOWEVER, the topic was about epoxy TIM that surely is not formulated for such super extreme cold. So there was that in my thought process. But also, it has been common practice for decades when removing a "stuck" CPU heatsink, running the computer for a couple minutes to heat up and "loosen" the bond would often make it easy (or easier) to wiggle the cooler and break loose that cured bond. So instead of by habit, getting the bond warm, sticking it in the freezer is what I meant by counterintuitive.

I have never bothered with any case air filters of any kind, the logic being that dust is truly insidious and gets in no matter what and the filters would just be more clutter and more stuff to clean.

Except that is not what happens in practice with a properly configured case. First and foremost, having the fans configured to provide a "slight" positive pressure (more air being pushed in than being exhausted out) ensures all the air getting into the case goes through the filters. That's critical.

When there is negative (under) pressure in the case (more air being exhausted than pumped in), a vacuum is formed inside the case. This vacuum cause dirty air to be drawn in from EVERY opening, including through every crack, crevice and unused USB port, video port, expansion card slot, etc. That not only brings more dust into the case, it also seriously contaminates those unused ports. Not good.

Sure, no filter is perfect. If a filter blocked everything, no air would get through either! So even with filters, eventually dust will still get inside.

And for sure, every user's operating environment is different - depending on the number of shedding animals (2 and 4 legged) running around the house, opening doors, hours per day case fans are spinning, HVAC filter efficiency, etc. But as a representative anecdotal example, with 4 humans and 2 dogs in the house, I used to have to tear down (disconnect all cables) and lug my computers outside for cleaning at least 2 - 3 times per year with my unfiltered cases. Now with my filtered cases, it is maybe once every 2 years.

"Gently" sliding out the filters for cleaning and washing is immeasurably more convenient and easier (especially on my back) than tearing down the computers and lugging them outside.