Ask HN: Does anyone have a VRAM tester? Something like MemTest86+ but for GPUs?
2 threads
This might help you: https://repair.wiki/w/Nvidia_GPU_Memory_Testing_Guide
For my Ebay GPU, I put this into Gemini "I got a used NVIDIA GPU. How can I test the GPU memory on linux with the cli?" and ended up using "gpu-burn" from the tools it suggested.