Any 3 Monitors Users??

[Mo75]

After installing my 3d monitor my gtx780 memory clock 6.01GHz all the time and GPU core 810MHz at least!!
Please Note:
- All the three monitors are 1920X1080 60Hz.
- If I disconnect any of the three monitors the clock will go down and rise only when needed.
- Clock down normally with the three monitors in windows so it's not a hardware limitation!.
- I tried Nvidia web driver the same result (actually Apple driver works better in most of application).
- I am on El Capitan but I tried Seirra on another driver and results are the same!.
- Machine currently on iMac 14,2 and working fine in everything else.
- I didn't find iMac 14,2 in AppleGraphicsPowerManagement.kext to try to change power state values, I don't know where to
start??
Big Thanks in advance

 

[Suloo]

hm, i also run 3 monitors. I got 7.01 GHz with 759 MHz with my gtx970. Is that bad thing? I thought everything is normal until now.

 

[Mo75]

hm, i also run 3 monitors. I got 7.01 GHz with 759 MHz with my gtx970. Is that bad thing? I thought everything is normal until now.

First Thank you for reply, it seems that it's very few people who running 3 monitors
Well the bad news is :
Yes your clock is high (we talking about idle here) you should get 324MHz clock core and clock only rise when you are using 3d application then go down again when you quit it or when you are on desktop or surfing the internet or so.. other wise you stressing your GPU for no need and will get higher GPU fan rpm and higher noise.
The good news is :
I solved this problem by my self , what I did is I disconnect one on the monitors of the video card and connected it to the integrated video card on the motherboard and this is not effected any performance here as far as I see (even in windows) it seems that it uses only the port of the motherboard but the 3d core all made on the discrete card (gtx970 in your case) in all of the three monitors (not so sure about that tho) just what I can see so far.
Well if you know how to do this good luck if you not sure please take a look at this thread :
https://www.tonymacx86.com/threads/hd3000-and-amd-graphics-working-together.45280/

Please note that the 3 monitors should be at the same resolution and the same MHz clock (60MHz for example) to get the clock down on idle other wise you will run into hardware limitation of Nvidia and nothing to do about it (may be only in windows you can solve that with 3rd party program called Nvidia Inspector but that's only under windows and in case if the 3 monitors dos not match).
I advice you to check your clock under windows by installing hardware monitor there (windows version for sure)
Good Luck

 

[Suloo]

oh wow, without the third monitor my card runs at 658MHz memory and 123MHz core frequency. Thats quite a difference yea. I'll try to activate the iGPU but i think there were some issues with running both on sierra. I also suffer from the Black Screen issue currently.

 

[Fl0r!an]

seems that it uses only the port of the motherboard but the 3d core all made on the discrete card (gtx970 in your case) in all of the three monitors (not so sure about that tho) just what I can see so far.

3D rendering will always be done on the GPU, which the monitor is connected to. So your GTX 780 will now power just two displays and the 3rd will be rendered by the iGPU.
Only excuse is Nvidia Optimus in Windows, but that's not possible in OS X.

 

[Mo75]

3D rendering will always be done on the GPU, which the monitor is connected to. So your GTX 780 will now power just two displays and the 3rd will be rendered by the iGPU.
Only excuse is Nvidia Optimus in Windows, but that's not possible in OS X.

Thank you for correction I was not sure anyway, but yes in windows it seems that no problems at all because when I run heaven benchmark test on the 3 monitors together at the same time (wall 3X1) I see no deferents, in OS X I can't run the same test, But well anyways I am so happy to get work like that with no load on GPU just to run the desktop .

 

[fiksni]

Hi all, indeed it seems that a small group of people use 3 monitors. However I use 2 monitor, and 3rd monitor is TV connected on HDMI. GTX 760 core was working on 810Mhz and memory on 6Ghz. I was trying whole week to find solution even with injectors but unsuccessful. Then tried to pull out 2nd monitor and graphic speed works normaly and find this post. Didn't try iGPU but it seems as great idea to solve this problem. I will try tomorrow, also didn't know that different monitors will make diference because 2nd monitor is 19" and main monitor is 27" also will check and write did it stuck.

If someone find solution, please post it...

 

[fiksni]

I found out next from my friend:

It seems that 3 monitors are supposed to work in SLI mode, respectively 2 GPU cards. When 3 monitors are used in 1GPU that is simulation and it works on Full Core Clock.

2 Monitors = 1 GPU - Idle Mode (Dynamic)

3 Monitors = 2 GPU - Full Core Clock
3 Monitors can go with 1GPU but that is because it simulates 2x GPU's and everything works on max. clock

I solved my problem by taking out HDMI cable from TV and connect it only when I needed and everything works great.
GPU now with 2 monitors is 135/648 Mhz.

 

[powerpcg5]

I didn't even noticed this, until I read this thread. I'm running 3 monitors and yes, 7 Ghz clock on GPU memory.
But the fans on my GTX970 are running very slowly (19rpm, 5rpm), so it's still cool temperature wise.

 

[slim.jim]

I didn't even noticed this, until I read this thread. I'm running 3 monitors and yes, 7 Ghz clock on GPU memory.
But the fans on my GTX970 are running very slowly (19rpm, 5rpm), so it's still cool temperature wise.

The 19 rpm is a bug in hardware monitor. They actually aren't spinning at all when it says that, the card has a semi passive cooling system.