Hi there everyone! This is my first time posting on the forums but I think its a very useful post. As many people who have the 770 might be aware there is no posted solution for the consistant crashing, this is where (for me) My main monitor would go black, sometimes going to sleep and my second monitor would turn a random colour. This would happen A LOT! for me, it could sometimes give me a good hour or two of gaming with no crashes, but on one particular night, it took me 6 hours to complete a 30 minute Guild Wars 2 mission due to having to restart due to crashing.
 
Ladies and Gentlemen, I am pleased to announce that after 3-4 days of testing, I have not crashed once. And its a super easy fix!
Please Note: I have two "Fixes" in place at the moment, but i'm pretty sure I know what fixed my card. I simply keep using the first fix because it ended up speeding my computer boot speed.
 
Solution(1): Some people have reported that conflicting services crashing the graphics card so this solution MAY solve the issue for you, for me personally it was solution two that fixed it for me.
Open up Run by pressing the left windows key and "R" at the same time, then type in "msconfig" without the quotes.

In the "General" tab and choose "Selective Startup"

Now move to the "Services" tab, Make sure to check "Hide all Microsoft services" BEFORE clicking "Disable all"

Finally navigate to the "Startup" tab and click "Disable all", then make sure to re-check "Microsoft OS"

Solution(2):
My second solution (The one that I'm 99.99% sure fixed this entire issue) was to update the graphic cards bios. When I first thought about doing this I was pretty nervous and I put it off for months, due to my lack of ever doing a process like this before, after going through this process I can tell anyone who might hesitate that its really nothing and its actually kind of fun! (nerd face). Just make sure to follow all the steps carefully! If you followed everything correctly with your fingers crossed your graphics card issues should have dissapeared!
 PLEASE NOTE: NONE OF MY LINKS WOULD DISPLAY SO I NEEDED TO GET RID OF THE "WWW." PART.
This is the Youtube video I used to learn the process of "flashing" my graphics card, Its very straight forward and helpful, you may need to turn the volume up though.
youtube.com/watch?v=94s_aAVtgb4
(This is not my video, all the credit for making it goes to "Libra Digital")
 
Also please note that some of his links didnt work for me so here are the ones i used that worked just fine! Also his version of NVFlash would return a error in DOS, a link to the version I used will be available below.
Note: Use these links along with the tutorial on how to set everything up and how to use them.
Links
NVFlash: guru3d.com/files_details/nvflash_download.html
Windows 98 boot files & HP USB Disk Storage Format Tool: vistax64.com/tutorials/191416-dos-usb-boot-drive.html
Gpu Bios: techpowerup.com/vgabios/
GPU-Z: techpowerup.com/downloads/2360/techpowerup-gpu-z-v0-7-8/