amd 8350
nvidia 970 SC ACX 2.0
ripjaws x series 8gb

i played for about 2-3 hours without crashing when settings were on high. i tweaked some to ultra and was able to play around 30-45 minutes without freezing. now i cant play more than 5 minutes without freezing.
textures on ultra. shadow, water quality, anything grass and foliage on medium. last freeze i had to hard reset my pc.

so. do i really need to put this game on high settings for it to function properly? i mean, its not even gonna make use of even a gig of the 970s 3.5 gigs of ram.

so someone pointed out that it might be an overclocking issue? how do i disable overclocking on my gpu?

If you haven't manually overclocked your GPU, you shouldn't have to worry. EVGA SC (superclocked) should be 100% stable at the built in overclocked settings EVGA selected. If it is not, then I regard that as a GPU fault and would recommend a replacement. However, you can change the GPU clock rate with Nvidia Inspector; an extremely nifty little program that I use on my Nvidia system:
http://www.guru3d.com/files-details/nvidia-inspector-download.html

For temperature monitoring consider downloading GPU-Z:
http://www.techpowerup.com/downloads/SysInfo/GPU-Z/

Open up GPU-Z and click on the "sensors" tab. Find "GPU Temperature" and click on the box to the right that has the temperature displayed within it until the box has a little green "Max" that appears in the box.

Now when you get into the game, this program will keep track of the maximum temperature without you having to alt-tab back out from the game.

It does sound like a temperature problem; with higher overclocks, higher temperatures can push an already overclocked hardware component to start to error out, though as a fellow EVGA SC owner (A humble GTX750), I would be upset to find the GPU failing at the manufacturers overclock rate.

its not an overheating problem. and i ran memtestCL on the card, its not a ram problem either. i run gta 5 max setting 60 fps for hours with no problems. there's something wrong with the game settings that are causing these crashes.

I have a similar PC as yours. I found this: https://youtu.be/vps9By3Q3lA

Cleaned up drivers with DDU and installed the February 10 nvidia drivers. Did NOT install Geforce Experience, nor the 3d vision drivers (do a custom install with the drivers not an express one).

Have played 2 times since doing the above, 60 minute each time (and streamed to twitch while playing (to a test server)). No crashes. But I cannot guarantee that this was the fix needed.

Also, I had PRELOADED the game then Galaxy patched it at launch.
I have now uninstalled the game (keeping my saves) and then reinstalled it via Galaxy. Not sure if this helped in any way, but thought I'd mention it.

My pc specs:
AMD 8350 cpu -> gaming + streaming = ~100% load on all 8 cores at 44 degrees C temp (with a CoolerMaster Hyper 412)
Gigabyte G1 970 -> gaming + streaming = 61 degrees C temp.
8 GB RAM -> gaming + streaming used up 6 GB
Crucial M500 250 GB SSD
Dual monitor setup (one on displayport the other on VGA)

No crashes, 47+ to 60+ FPS while playing AND streaming (+10 addition fps when NOT streaming)

Also, make sure to disable HairWorks and Hardware Mouse Cursor (set it to off) and use SSAO and not HBAO+. Also I ran the game on HIGH, framerate = unlimited, borderless window or fullscreen (try one and see if it's stable)

Hope you get to enjoy this game, 13 hours of game time here (out of 24 available in a day), I love it! Really, really good game.