RTX 4090 48GB VRAM Modded GPU In China Tested; Check Results

RTX 4090 is available with 48GB VRAM in China. Find more about the features, testing results, and other details here!

Nvidia’s GeForce RTX 4090 is quite the behemoth of a graphics card, even in 2025, after the RTX 5090 came out. Given its prowess, its usefulness expands beyond gaming into many other applications, including meeting the compute requirements of AI workloads.

People recently discovered that manufacturers are rebuilding the RTX 4090 to upgrade its VRAM capacity to 48GB and then resell it to customers. Technicians modify former RTX 4090 or RTX 4090D graphics cards produced by board partners such as Gigabyte, Asus, MSI, and others. Nvidia manufactures the RTX 4090D specifically for the Chinese GPU market and lowers its performance to comply with U.S. sanctions. Finally, technicians dismantle and rebuild the GPUs with a new cooler, and customers frequently deploy them in massive AI farms in China.

The Modded RTX 4090 with 48GB VRAM, which is an unofficial graphics card, was recently acquired by Мой Компьютер, a YouTuber from Russia. Tests were conducted on the graphics card, revealing interesting results regarding its functionality as well as its prowess in gaming.

Testing Results of RTX 4090 48GB VRAM Modded GPU From China

Of course, 48GB of VRAM is completely overkill for gaming and general usage. But could somebody use this as an individual GPU for their PC rather than an AI compute farm? Definitely not! In testing, this modded GPU was shown to have insanely high noise levels, reaching up to 65 dB. Normal levels are approximately half of this, depending on the PC.

Modded RTX 4090 48GB VRAM Temperature and Noise Levels testing (Image via: YouTube @Мой Компьютер)

This is because the cooler is designed to save space, being a blower-style with a single fan. GPUs built in this way typically have high noise levels. The card was even tested in 3DMark and Blender. While this may be one of the best RTX 4090 GPUs available, gamers shouldn’t spend their efforts acquiring a GPU like this. Still, the modification is very cool to see.

Modded RTX 4090 with 48GB VRAM tested in Black Myth Wukong (Image via YouTube @Мой Компьютер)

The graphics card was also shown in action playing games, consuming around 300–350W, with presumably core temperatures hovering around 60°C. When tested in the Black Myth Wukong official benchmark, the GPU was able to output 84 FPS at 5120 x 2880.

RTX 4090 48GB VRAM Modification With Liquid Cooling Is Available in China, Too

Moreover, someone also made an interesting modification to these unofficially modded 48GB VRAM RTX 4090 GPUs—the addition of liquid cooling. It looks like the radiator is 360mm with triple fans, and a pump is externally present as well. A Reddit user posted more information, claiming that this GPU is cheaper (reportedly $3,400) compared to the current market quotes for the RTX 5090.

Modded RTX 4090 with 48GB VRAM is also available with liquid cooling (Image via: Reddit) — Modded RTX 4090 with 48GB VRAM is also available with liquid cooling (Image via Reddit)

The GPU is extremely slim and has the text “GeForce RTX 4090 48GB” written on it. It’s fascinating to see such wild GPUs being made and the possibilities in China. In any case, whether or not the RTX 4090 48GB is a good GPU for the price, it is not something a normal user should buy. These GPUs do not come with official warranties from brands either.

Instead, we recommend going with the RTX 5070 Ti, RTX 5080, or RTX 5090—whichever is most affordable for you. If you need the kind of VRAM capacity that is only offered on top flagships, finding an RTX 4090 at a discounted price could be a good idea as well.

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