This 4090-equipped water-cooled copper PC 'looks like a steam engine' and I'm in love

Two pictures of Billet Labs' copper gaming PCs
(Image credit: Billet Labs)

Have you ever seen a water-cooled copper gaming PC before? If not, you're in for a treat as an absolute beauty named "the boiler" has just been shown off by builder and retailer Billet Labs. And it's for a good cause as its auction proceeds will be going to charity once it is sold.

In the TikTok video showing it all off, the machine had not yet actually been turned on, as the team still had to fill it with water. The presenter says it "looks like a steam engine" and I don't think I could come up with a more apt description, other than it could be strapped to the waist of a steampunk cosplayer at Comic-Con.

Just days after this video, Billet Labs posted a follow-up to it on Instagram not only announcing that the PC turned on successfully but that "it works really well". Alongside this, a full build video will be going live on the Billet Labs YouTube channel this Wednesday.

This copper PC is currently fitted with an RTX 4090 Founders Edition graphics card and an AMD Ryzen 7 9800X3D, which is currently our pick as the best gaming CPU. It also has 64 GB of RAM, 12 TB of SSD storage and has a Noctua fan on the top, that has been stripped and polished. All of the copper piping in the build is hand-soldered together to a water pump to keep it all cool.

Copper has both a pretty look and is a great element for thermal conductivity. There are some performance gains to be had in a build like this, even if it feels nearly impossible to upgrade, should you get your hands on one of the seemingly handful of RTX 5090s out there.

Billet Labs has a now sold-out MonoBlock which is compatible with 3090 Ti FEs and 4090 FEs and cools both the CPU and GPU, which originally got eyes on the company due to a controversy involving tech YouTuber Linus Tech Tips in 2023. However, the site also sells pipes, pump tops, and fittings to start building your own water-cooled copper rigs.

If you don't fancy taking part in the auction, Billet Labs does take commissions for PCs. Just last year, it unveiled a Toaster PC, which took £5k / $6.2k in parts alone, plus over 150 hours worth of work to build.

Both the steam machine build and toaster build are very small in form factor, which seems to be something the copper water-cooling is uniquely good for. Putting parts close together can make cooling less efficient and copper being particularly efficient with cooling can counteract that. We don't yet have word on an RTX 5090 build or how compatible these machines are with upgrades (I'd think the specificity of the build would suggest not very) but I personally can't wait to see what they look like when that copper oxidizes. It's like a mini PC that just keeps on giving.

I certainly don't need one but I do want one.

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James Bentley
Hardware writer

James is a more recent PC gaming convert, often admiring graphics cards, cases, and motherboards from afar. It was not until 2019, after just finishing a degree in law and media, that they decided to throw out the last few years of education, build their PC, and start writing about gaming instead. In that time, he has covered the latest doodads, contraptions, and gismos, and loved every second of it. Hey, it’s better than writing case briefs.

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