They are not all created equal. Built a machine for my son's friend using an MSI GTX 970. Crisp, clean, no temporal dithering. No eyestrain. Just pure awesome.
Rebuilt my own desktop - finally giving up on my venerable GTX670 - with a Zotac GTX970. It's ... not horrible but hard to look at. Not instant headache like an AMD would be but not great. It could just be that my old monitors (2011-era LED HP 23") are not up to the task of dealing with the new card. Or maybe Zotac just isn't as great as MSI. The Zotac literature says they use some kind of "4k on a 1080 display" technology which sounds suspiciously like dithering, so that might be at play as well. Not sure if that's a Zotac thing or an nVidia thing but it sounds terrible.
I'm trading the Zotac in for a (much better) EVGA GTX970. I went with the 970 because the new 10x0 architecture doesn't have Temporal Dithering turned off by default (and we don't have an nVidia version of "ditherig").
Thoughts? I've never had issues with these monitors (the pair of HP's) before, but I could always swap for a Dell or two until I find just the right thing to buy.