I currently prefer (and continue to purchase and upgrade) nVidia.
Many years ago, I had purchased an ATI "All in Wonder Pro" card and was left with a bad impression since one of the games I played often had bad issues with screen artifacts. My experience wasn't too great with the ATI technology, the company of course, now owned by AMD. I definitely purchase AMD CPUs, however, because the graphics card is really what tends to be the bottleneck and you get more bang for your buck with the AMD processors.
As an alternative video card solution to ATI, I went with the 3dfx Voodoo cards which were great for their time and ever since nVidia had purchased their assets, I had started and continued to buy nVidia ever since.
I'm kind of dating myself now, but I remember when the Hercules graphics card was the bomb; although monochrome, it had the best resolution out of the CGA/EGA cards at the time. I remember playing Ford's "Test Drive" with a Hercules card and it looked better than the decent EGA versions.
It wasn't until VGA came out with the VESA standards where graphics really started becoming more appreciable --I'm really glad that someone saw there was opportunity to just make an industry out of graphics technology, it just seemed like the natural progression.
Play a game like "The Witcher 3" nowadays and then go back to play some emulated Atari nostalgia, you get tired of it really quick. However, playing video games on your TV back in the 70's (yeah, the good old
pong, jai alai and skeet shoot light gun) was the hottest thing since sliced bread.