Homebrew RTX 3080 passive cooler is a 23 pound copper block

If you want any kind of power in a modern PC build, you’re going to have to move some air around at some point. That’s one of the fundamentals of computer hardware: Barring a super-portable laptop or a teeny-tiny desktop the size of a Rubik’s cube, you need fans to cool your components. Unless, of course, you’re ready to strap about 25 pounds of metal to it and turn it into a very expensive radiator. Just ask this Reddit user, who’s attempting to passively cool an Nvidia RTX 3080.

The post outlines one person’s attempt to get a high-end graphics card to operate without any kind of moving parts, removing the stock cooling shroud and replacing it with a Frankenstein monster of copper and steel. The passive cooling aficionados at Fanless Tech spotted the post (via Tom’s Hardware). The user says their contraption is made from a solid bar of copper, one foot wide, two inches tall and three deep, with what looks like at least eleven extra CPU cooler heatsinks attached to it. Sans fans, of course. They’re not permanently affixed — the project is still at the planning stage.

I did some napkin math, and the copper block alone weighs 23.26 pounds, 10.55 kilograms. It’s dwarfing the beefy RTX 3080 GPU and PCB beneath it. Good thing it’s not actually installed, because I don’t know of any motherboard that could take it without snapping in two, even if you could fit in a custom case. Of course any working build would use a long riser cable.

Based on user EveryNameTaken9’s comment history, it seems like they’re a long way out from actually getting this thing to work, despite completing a couple of passive cooling projects before. The consensus among the comments on the post seems to be that the huge bar of copper won’t be able to effectively dissipate the heat from 350 watts of power in the card, effectively sitting on top of the GPU like a cast iron pan on a stove, making the extra heatsinks superfluous. EveryNameTaken9 says they’ll build a horizontal variant next, allowing the heat to rise naturally, and possibly try drilling holes for more direct heat pipes.

There’s a small but dedicated group of PC fans enthusiasts who like to try and passively cool high-power components. There are even a few commercial products that appeal to the niche, like SilentPC’s passive cooling designs, some of which can even fit high-end parts like a Core i9 into an ATX desktop case. But even those options can’t handle a card as powerful as the 3080 without a fan, topping out at the RTX 4060 Ti and using the stock cooler. Maybe solid-state cooling will usher in a new generation of designs…but it won’t be for a few years at least. And passive fans might scoff at it anyway, since it still uses a tiny amount of electrical power.

Author: Michael Crider, Staff Writer