So, because of the ethereum boom, it seems that the only way I'm going to get a gtx 1070 is to go onto ebay or craigslist. When looking through these listings it seems many people claim things like "oh it's completely new I just opened the box to take the picture" or "oh it's only been used for a week", which seem like lies they tell to hide that they've been using the gpu for a year. Is there a way to see exactly or approximately how long a gpu has really been used?