That's the thing i don't get when people are bashing nVidia.neither are the stock Apple drivers.
With GT220 to GTX980 (that is right now in my cMP) the biggest problems i had are few pixels going mad, and the last time it happened was in El Capitan.
On the other hand i've had numerous screen glitches with HD6850 and more than few system reboots/crashes with HD7950 (official) and R9 280X caused by Apple AMD Controller and Framebuffer kexts.