https://www.pcgamer.com/gpu-z-will-now-tell-you-if-the-nvidia-graphics-card-you-bought-is-a-fake/

TechPowerUp has updated its GPU-Z utility to detect "fake" graphics cards so buyers of second hand GPUs can tell if they've been scammed.

This was apparently a thing during the cryptocurrency mining boom that saw graphics cards selling at inflated price tags, sometimes double or even triple the MSRP. Unscrupulous sellers took advantage of the situation by flashing lower end cards to appear as higher end ones.