Water Cooling a GPU Without a Cold Plate

When you’re really serious about squeezing every little bit of performance out of your computer, heat becomes a huge issue. A chip that gets too hot will either be throttled or fried, so high-performance cooling systems are a must in these cases. Air cooling might work for most setups, but when pushed to a certain point, only a water cooling system is going to be able to remove heat quickly enough.

The basic idea behind these systems is simple enough: pump a steady stream of cool water over a chip to shuttle heat away. But in practice, things get more complicated. The thermal interface, in particular, is hard to perfect. Any gaps between the chip and the water block will significantly impact cooling performance. Similarly, thermal paste can hinder performance if it isn’t high quality and applied correctly.

Matt from the TrashBench YouTube channel wondered if he could bypass all of this complexity and simply flow water over the top of a GPU chip. That would normally be a really, really bad idea for obvious reasons, but he came up with a few hacks to make it actually work. Naturally, you can’t find a system like this off the shelf, so Matt had to build it from scratch.

The first problem was keeping the water away from everything except the silicon die. Tap water is conductive enough to cause plenty of trouble on a powered graphics card, so Matt covered the tiny surface-mount components and electrical contacts surrounding the GPU with nail polish. This created an insulating, waterproof coating while leaving the silicon exposed.

Next, he designed a hollow 3D-printed chamber that could be epoxied directly around the GPU. An early version printed with clear filament leaked because water could work its way through microscopic gaps between layers. Switching to PETG and adjusting parameters such as extrusion flow, line overlap, and wall thickness produced a watertight version. Hose fittings were then installed and reinforced with epoxy.

After experimenting on a dead RTX 3060 to check for leaks, Matt moved on to a functional GTX 980. Fortunately, nothing went “pop.” The card powered up and ran normally with water flowing directly across its exposed die.

The real test came with an RTX 2060 Super. Its stock air cooler allowed the GPU to reach about 70°C under load, while an ARCTIC AiO liquid cooler dropped that to roughly 36°C. Matt's direct-die setup matched or slightly beat the AiO and survived both UNIGINE Heaven stress testing and Cyberpunk 2077.

Epoxying plumbing directly onto a graphics card probably isn't going to become the next big thing in extreme PC cooling. But the experiment showed that removing the cold plate and thermal interface entirely can actually work quite well — provided you can keep the water where it belongs.