In a recent GPU scam uncovered by a Chinese technician and YouTuber, a customer discovered that three of the GeForce RTX 4090 cards he purchased were actually modded RTX 3080 and 3090 GPUs. Despite being sold at premium prices, these fakes had cleverly disguised exteriors that could easily fool an average buyer. 
The technician’s in-depth teardown revealed several telltale signs, from substrate inconsistencies to misplaced QR codes and suspicious capacitors – all pointing to forgery.
The three fake GPUs had “AD102” engraved on their dies to mimic the genuine RTX 4090 chips, but the engravings were likely modified using laser tools after erasing the original markings. One card even had fake VRAM installed, while another had such poor construction that its frame wasn’t secured properly. The customer paid around 10,000 Yuan (~$1,400) per card, believing he had scored a deal on flagship-level performance – only to be deceived by overseas sellers.
Luckily, a fourth card turned out to be a genuine RTX 4090, though it initially failed due to faulty capacitors and memory chips. After repairs by the technician, it worked fine. Unfortunately, the other three units were unsalvageable.
This case is another reminder that even savvy PC enthusiasts can fall victim to counterfeit hardware, especially when GPU prices are sky-high and the market is flooded with too-good-to-be-true offers. With modding techniques becoming increasingly advanced, identifying fake GPUs now requires a trained eye – or a teardown.
For those shopping for high-end graphics cards, sticking to reputable sellers and being wary of suspiciously low prices is more important than ever.