well the 570 i had one day it crashed and froze my pc, and when i rebooted it, it was in a low resolution. I went into device manager and it said error 42. Due to this i tried everything different pcie slots, different drivers but nothing worked. So i sent it off to the manufactuer where they have to test it to send me a new one. They sent me back a "b grade" 670. This means its most likely refurbished. When i got the card it had some sticky residue blotches on top of the card. So i plugged it in and it had a black border around the display. In device manager it noticed it was a 670 so i installed the drivers, rebooted and it kept rebooting itself after starting windows. I installed the drives in safe mode and it no longer knows theres a 670 in here and when i manage to get on my pc with the drivers installed the nvidia control panel says no nividia gpu is detected.
Once again i tried the different pcie slots and reinstalling windows and upgrading the bios but with no luck, now im running onboard graphics and everything works great.