My trusty Radeon RX 580 has served me well, I've used it a couple of years now but some of the work I'm now doing needed something more powerful I've kept the card as clean as i can, and I've always had the unused ports blocked off. I've been able to play everything i wanted to including Stalker 2, Helldivers 2, Mecha Break etc on reasonable settings so as long as you have a decent psu and processor this run nicely.
eBay