A Russian repair specialist known as VIK-off recently examined a bare RTX 4090 PCB that a customer had bought for 30,000 rubles, about $350, as a repair project. Because the original cooler was missing, the buyer could not verify the card worked before purchase. The specialist found the board was fitted with dummy components designed to look genuine.
The counterfeiters replicated the GPU package, chip markings, and surrounding compound, and even soldered the fake die using ball grid array. However, subtle clues such as substrate color, surface reflections, and lettering gave it away. After removing the fake package, the contact area did not resemble a functional processor, and the solder mask began to deteriorate during cleaning.
The memory chips initially looked authentic, but removing one revealed GDDR6 memory rather than the GDDR6X used on real RTX 4090s. The markings closely resembled genuine Micron packages. VIK-off suspects the PCB might be based on an RTX 3090 Ti, though there is no conclusive proof. This follows a similar scam in June where a broken RTX 4090 had a plastic imitation of Nvidia's AD102 die.
The case highlights the risk of buying used high-end GPUs, especially those listed as repairable or untested. The article advises asking for proof that the card works and testing it in a system before paying.