Best gpu for $300-350

I'm currently running an r9 390, i5-6500 with 16gb of ram and an ssd for boot and a few select games.

I originally bought the 390 and upgraded to 16gb ram because I used to do rendering, though I don't render anymore. Seeing as AMD cards are much better at working with most cryptocurrencies because of how they solve problems, it could be in my best interest to go with a different card since prices are inflated.

I recently moved out of a room that was constantly ~60 degrees F into one that's usually 80 F. I've since dropped from 100 fps to 40-60 (stutters a lot) when I play Player Unknown Battle Grounds. Would it benefit me to sell my card and get an nvidia within ~50-75 bucks from selling price (completed eBay listings are 300-350)?

After getting my 390, I haven't looked at performance of other cards much, but I am aware that new card generations came out shortly after and left me sad heh.

So let's say a budget of 350-400 dollars, wat do.

Also, ways to cool down my set up are an option, but I know water cooling a gpu is more of a hassle.