Running iMac screen at 50Hz - Is it safe?

[beauchampboiler]

Hello! I've already posted this on MacRumours but wasn't able to get a response. Hopefully I'll have more luck here.

I'm trying to get smooth playback of 25/50fps BBC iPlayer content on my 27'' iMac, currently used as the main 'TV' in the house (I live in the U.K.). I used a program called SwitchResX to define a profile of 2560 x 1440 @ 50Hz and set Kodi to change refresh rates to match content. At first, this all appeared to work perfectly with Kodi automatically switching from 60 to 50Hz when watching iPlayer content, which improved the smoothness considerably.

However, after exciting Kodi I noticed a slight but noticable flicker when on the login screen, (even though the screen was presumably back in 60Hz mode). This mostly went away after a restart.

I've already got this working on my Windows PC, but this has an external monitor. As my iMac's screen is internal, I am concerned that it may be damaged by running it at a lower than intended refresh rate. It would be great if someone with knowledge about iMacs and/or LCD screens in general could tell if there is any danger in doing this.

Thanks for your help .

 

[Cory Cooper]

Hello and welcome.

I don't believe it will harm your display, since it seems to be working properly. It may merely cause the flicker that you mentioned when you exit the app. You may need to restart each time to set the refresh back to 60 Hz.

You could always check with Apple themselves to be sure, since there isn't a built-in setting to change the refresh rate of the iMac's screen in the Display preference pane. Or, soy u could attach an external to the iMac and display the video there, instead of on the built-in panel.

Hope that helps.

C

 

[beauchampboiler]

Hello and welcome.

I don't believe it will harm your display, since it seems to be working properly. It may merely cause the flicker that you mentioned when you exit the app. You may need to restart each time to set the refresh back to 60 Hz.

You could always check with Apple themselves to be sure, since there isn't a built-in setting to change the refresh rate of the iMac's screen in the Display preference pane. Or, soy u could attach an external to the iMac and display the video there, instead of on the built-in panel.

Hope that helps.

C

Thank you for your response, that's reassuring. I'll probably check with Apple to be sure as you suggest. It seems strange to me that computer manufacturers make this so difficult to do when you consider how much of the world uses 50Hz for TV broadcast.

 

[Cory Cooper]

No worries...please let us know what you find out.

C

 

[beauchampboiler]

I decided to risk it in the end. All working well so far including 47.952Hz for films.

 

[Cory Cooper]

Excellent...glad it's working for you.

Enjoy,

C