I bought this graphics card secondhand a few months ago. I didn't have any issues up until recently after I swapped my motherboard and CPU. I went from a Z270/7700K to a Z370/8700K (bought 2nd hand as well). Reason I mentioned the hardware change is because I did not do a clean install of Windows and I heard that could be a problem. Thoughts on that? 
 
The issue I am experiencing are game crashes and in some cases artifacting after about an hour of play. There are some nights I can play for like 2+ hours without any crashes. When it crashes, most of the time I can go back to the desktop (even when it artifacts). In some occasions, the whole system will rest.
 
There is no manual overclock. I think its a memory issue, possibly the memory getting too hot. Temps during gaming is 75C and the memory is more or less the same, maybe a little bit higher. Ambient temps have been pretty warm this week, located in CA. I'm creating this thread because I need help with troubleshooting this. I plan to use this until I can get a brand new 3000 series card, so I want to do whatever I can to hold me off until then.
 
Should I try underclocking the memory and core clock, power limit? I ran the GPU memtest and it didn't find any issues. Last weekend I replaced some thermal pads and repasted the GPU. I ordered some more thermal pads and will replace the rest of them this weekend. I will try the NVIDIA debug mode tonight. Any other advice or tips is appreciated!
 
Current installed driver is 442.59, I tried updating to the latest one and it seems to have been a lot worse so I rolled it back
 
I ran unigine heaven 4.0 (can pass 90%) of the time, ran Furmark for maybe 30 min without any crashes and Timespy (completed with high scores)

No luck on the Debug mode, however, I lowered the power limit to 80% and did not get any crashes. The temps were significantly much better even in my very hot room. When I compare the artifacting crashes to those online, it definitely seems to be related to VRAM (see image below, not mine but same look) Underclocking that by itself did not help when I was at 100% power limit. PSU was purchased new and is an EVGA G3 650W. I will keep playing tonight and may try more troubleshooting in the morning once it's not too hot. I still intend to replace the rest of the thermal pads once I receive them in the mail. 

 

evola196
it definitely seems to be related to VRAM

 
True story.
 
How To RMA  
EVGA Warranty Questions 

https://www.evga.com/warranty/check.asp

wow i had the exact same problem with my 1080 ti card.when i lower the power limit to 80% no more crashing in any games.i justed  rma the 2nd card like that.the 1st card was the same issue.so i got the 2nd card and i had the exact same issue.i did all the trouble shooting steps even going as far as a fresh install of windows nothing worked.i rma the 2nd card last week before my warranty is up hoping i get a 1080 ti that wont do the same thing or maybe a upgrade but i am not holding my breath.i went out and bought a xfx 5700xt while i am waiting for my replacement card and guess what on the new xfx 5700 xt?no crashing during games or artifacting.i am hoping evga wont send me another lemon before my warranty runs out.