Buyer pays $350 for broken RTX 4090 project only to find realistic fake GPU die and swapped memory — Russian repair specialist reveals sophisticated new cam using dummy PCBs

A GPU repair specialist has uncovered another GPU scam involving a counterfeit RTX 4090, with a fake GPU die and memory chips designed to resemble genuine components. The graphics card was purchased for 30,000 Rubles, or approximately $350, as a potential repair project. However, upon close inspection, it was revealed that the board was fitted with dummy components.

According to VIK-off (h/t VideoCardz), the Russian repair specialist received the GPU from a customer who purchased the card as a bare printed circuit board (PCB). Since the original cooling system was missing, it was difficult to verify whether it actually worked before the purchase was made. Now we’ve seen similar scams in the past, but this particular case stands out due to the sheer effort that was put into making the counterfeit components.

According to Vik-Off, the counterfeiters managed to replicate intricate details including the labeling, GPU package, chip markings, as well as the compound surrounding the processor. The fake GPU die was even soldered onto the PCB using a ball grid array (BGA), making it appear as though it had been installed during the original manufacturing process.

However, certain inconsistencies gave it away, like the color of the substrate, surface reflections, and certain lettering. After removing the fake GPU package, the repair specialist found that its contact area did not resemble that of a functional processor, while the solder mask started to deteriorate during cleaning.

Even though the memory chips looked genuine at first, removing one of the packages revealed what appeared to be GDDR6 memory rather than the GDDR6X chips used on the RTX 4090. The markings on these chips closely resembled genuine Micron memory packages, making the counterfeits even more difficult to identify. Vik-Off suspects the PCB design could be based on an RTX 3090 Ti, although there is no conclusive proof.

This isn’t the first time a counterfeit RTX 4090 has made its way into the hands of customers. Back in June, Chinese hardware shop owner Brother Zhang came across a broken RTX 4090 that had been purchased for around $222. A closer inspection revealed that the card was essentially a replica with a plastic imitation of Nvidia’s AD102 GPU die instead of the actual silicon. Additionally, the "TW 3043E2" marking indicated that the card was somehow manufactured in 2030.

One should always be cautious when purchasing used high-end graphics cards, especially those marked as repairable or untested. The onboard components and chip markings might look convincing, but that does not guarantee that the hardware inside is genuine. Always ask the seller for proof that the card works and, whenever possible, drop it in a system and test it before handing over your money.