GTAV - turned off v-sync, GPU fan went insane

[sno0ks]

I briefly turned off v-sync to see what it would do. It was indoors at the car dealership, which is reflection-heavy. My fans then went so loud it sounded like a jet engine. I immediately turned v-sync back on and it went away. Did I just damage my cards? 2x GTX 970s SLI.

 

[Justin Millard]

Nah, the fans just sped up because V Sync was causing them to only do the work needed for 60FPS.
When you turn V-Sync off they go to work creating as many frames as possible and start to heat up.

You could try using frame rate target instead of V-Sync.

 

[sno0ks]

Nah, the fans just sped up because V Sync was causing them to only do the work needed for 60FPS.
When you turn V-Sync off they go to work creating as many frames as possible and start to heat up.

You could try using frame rate target instead of V-Sync.

I've never heard of Frame Rate Target. Is that a program or a setting?

 

[mrmez]

Nope.

V-sync limits your fps to your monitor's refresh rate. Usually 60fps/hz.
With a fast card and v-sync on, the card doesn't max out, as its capable of performing better.
Turning v-sync off removed this restriction and lets your card perform as fast as it can. This causes more heat, which causes the fans to ramp up.

The 970 isn't known for being a loud or hot card, but depending on the brand and your setup, the extra heat could have been enough to cause the fans to run flat out, especially with an aggressive fan profile.

 

[sno0ks]

They're both OC'd, and they can idle anywhere from 28-40c depending on ambient temp.. It tends to peak around 80-82c. They peaked at 89c during that scary moment, and I didn't notice an improvement in framerate when it happened. There was some choppiness, which is why I turned off reflection MSAA, which helped a little. They have +6mV with a high of 90-91c, but I've never seen them get that high. I'm getting an AC unit tomorrow, which I hope will lower these temps.

As for fan profile, I just have it set to AUTO in Precision.

 

[sno0ks]

I wasn't sure if the sudden drastic change in temp was a bad thing. It was literally silent and then instantly going as hard as it could go.

 

[Justin Millard]

Don't worry about it. Your temperatures didn't get scary high. The GPU can handle that in short bursts. You probably don't even need to use any anti aliasing with that setup as it tends to make graphics slightly blurry. Anti-aliasing is a waste for resolutions above 1920x1080.

Although Dynamic Super Resolution is usually the best form of anti aliasing as it renders at a higher resolution guaranteeing the best quality picture when it is shrunk back down to your native resolution.

You can use Frame Rate Target in third party applications like EVGA Precision X to set a max frame rate.