[Bikkuri]

Not so sure about that.. I have read a few stories, within the last couple of months, that all of the good NVidia cards are being sold (to the miners) faster than the public can get their hands on one (for gaming).
This is the reason I went ahead and purchased an RTX (instead of GTX) 2060 at the beginning of this year.

[Shadylake]

It’s a shame, this 3xxx is basically a skipped gaming generation. By the time the 4xxx’s are out, they 3k’s will be worthless for gaming.

[palmer]

To clarify: they are not used for mining bitcoin . OTOH graphics cards are currently used to mine ethereum. That's because they supprt the high memory bandwidth needed for ethereum. Bitcoin doesn't need high memory BW just fast SHA256 hashing. No GPU comes close to the custom hardware used for SHA256. So no GPUs are used for bitcoin or bitcoin clones.

However, ethereum is going to switch to proof-of-stake so all those graphics cards will no longer be useful. There are clones of ethereum that require high memory BW (and clones of bitcoin that require bitcoin HW). But those clones are not nearly as popular and won't create as high a demand.

If you can take a profit on your graphics card, I would do it before the switch-over to PoS.