iMac to samsung "mode not supported"

[ruk110]

I have a 21.5 inch iMac and have it hooked up to a Samsung LED 40inch tv. its been connected and forking perfectly for some time now. but i had to disconnect the mac for a day and now that i have gone to re connect it, the tv shows 'mode not supported' The resolution is not supported on this TV. Please change the resolution.

the TV is a full Hd 1080p one and so is my mac settings set to 1080p and 60hz to match the tv, but its not working anymore! any ideas on how i can get past this problem? or is it a fault with the mac/TV??

[maxmiles]

I have a 21.5 inch iMac and have it hooked up to a Samsung LED 40inch tv. its been connected and forking perfectly for some time now. but i had to disconnect the mac for a day and now that i have gone to re connect it, the tv shows 'mode not supported' The resolution is not supported on this TV. Please change the resolution.

the TV is a full Hd 1080p one and so is my mac settings set to 1080p and 60hz to match the tv, but its not working anymore! any ideas on how i can get past this problem? or is it a fault with the mac/TV??

1. Make sure the TV is set to the proper HDMI or VGA port.
2. Check the cable connections, unplug and replug on each end and make sure each are secure.
3. Experiment with the resolution settings on the iMac, maybe something changed and whatever particular mode it's set to is not recognized by the TV.

[ruk110]

Tried checking all connections are ok. tried out all four HDMI ports and still same message and changing the resolution on my mac just makes my screen go big and small but TV still does not display anything at all

[maxmiles]

Tried checking all connections are ok. tried out all four HDMI ports and still same message and changing the resolution on my mac just makes my screen go big and small but TV still does not display anything at all

How about the refresh rate? Make sure it's at 60Hz

[shoulin333]

How about the refresh rate? Make sure it's at 60Hz

Or sometimes with my screens you can choose 59Hz and that seems to work better than 60 for some reason.

[ruk110]

How about the refresh rate? Make sure it's at 60Hz

still not woking, im going to back up using time machine and see if that makes a difference,wish me luck...

[maxmiles]

Also try cycling through the ports on the TV, that might jog it to work. (I mean press the input button on your TV remote to move it through the different video-in connections.)

[maxmiles]

still not woking, im going to back up using time machine and see if that makes a difference,wish me luck...

Time machine is totally unrelated to the video out issue. Or I suppose if using time machine you return your monitor settings to what was working, maybe? But it's important to find out exactly what settings have been changed to break the connection.

[ruk110]

OMFG now time machine is nor working. as i enter it the 'restore' button is greyed out so i cant even restore to the previous settings. scrolling through the different ports didnt work. same message. frustration.

[maxmiles]

OMFG now time machine is nor working. as i enter it the 'restore' button is greyed out so i cant even restore to the previous settings. scrolling through the different ports didnt work. same message. frustration.

I hear ya.

Mmm.. if this was a connection problem it would say "no input" or something similar. It's got to be a settings issue. I have a samsung 37" and might connect my macbook to it to see if I can better see what the setting selection is. Am out-and-about right now, will test it in a few hours.

[AlphaDogg]

the issue here could be with the adapter or hdmi cable you are using. try replacing both the adapter and the hdmi cable... it might have worn out over time, resulting in your frustrating issues.

[ruk110]

the issue here could be with the adapter or hdmi cable you are using. try replacing both the adapter and the hdmi cable... it might have worn out over time, resulting in your frustrating issues.

i tried another hdmi lead and still nothing,i dont have another adapter but tried wiggling it around and did not prove not make any difference. i know the tv is working fine because i have my playstation hooked up to it right now :(

[Hellhammer]

@OP: Try repairing permissions with Disk Utility. Also, is there any chance that the adapter isn't working? Try PRAM and SMC reset too

[ruk110]

@OP: Try repairing permissions with Disk Utility. Also, is there any chance that the adapter isn't working? Try PRAM and SMC reset too

pram and smc?? and how would i go bout doing that?

[Hellhammer]

pram and smc?? and how would i go bout doing that?

http://support.apple.com/kb/ht1379
http://support.apple.com/kb/HT3964

[maxmiles]

So I've connected my macbook to my samsung HDTV and can't see any settings that you could be missing or might cause this. Mine is set to "1080p" as the resolution, and I'm sure you've tried this numerous times.

Question: is your iMac able to detect what the device is? In the display preferences do you see the extra dialog box called "SAMSUNG"?

[maxmiles]

man, I should just invest in something like GoToAssist so I could see exactly what is on a person's desktop. Has anyone ever tried using these remote access programs? pretty useful.

[JustSomeDude]

These two blog posts refer to your problem and offer a solution:

http://chriscurtis.org/weblog/entry/mac-to-samsung-tv-via-hdmi-and-mode-not-supported/
http://chantc.blogspot.com/2008/05/reset-resolution-of-lcd-tv-display.html

[maxmiles]

Ok, this should work:

In display preferences click on "gather displays". What happens?

[JustSomeDude]

Ok, this should work:

In display preferences click on "gather displays". What happens?

Doh, I didn't notice you were doing this off an imac earlier (although, my display preferences says "gather windows")

Ignore my advice (since it requires another computer). Maxmiles advice does the equivalent, but much easier. Anyway, according to the blogs, the mac is detecting your samsung and trying to set Pal mode (50 hz) automatically. So using Maxmile's advice you'll be able to get the settings for the samsung and set it correctly.

[ruk110]

man, I should just invest in something like GoToAssist so I could see exactly what is on a person's desktop. Has anyone ever tried using these remote access programs? pretty useful.

trust me if could screen share with some sort of expert id jump straight up and share it for remote access but the help just is not around these days.

[ruk110]

Ok, this should work:

In display preferences click on "gather displays". What happens?

*tumble weed flys across the room*

nothing what so ever

[ruk110]

So I've connected my macbook to my samsung HDTV and can't see any settings that you could be missing or might cause this. Mine is set to "1080p" as the resolution, and I'm sure you've tried this numerous times.

Question: is your iMac able to detect what the device is? In the display preferences do you see the extra dialog box called "SAMSUNG"?

yes my iMac does detect the Samsung as a display but then thats about as far as it all goes. if i click on any lower res setting my mac blinks and changes but the tv sort of just sits there

[JustSomeDude]

*tumble weed flys across the room*

nothing what so ever

Try "detect displays" and then "gather windows". You should see a 2nd display preferences windows pop up behind your current one. This should have the display settings for your samsung.

[ruk110]

Try "detect displays" and then "gather windows". You should see a 2nd display preferences windows pop up behind your current one. This should have the display settings for your samsung.

nah done that one too. i have done just about everything there is to do. now im thinking to go back in time a week ago when everything was peachy?

..time machine is only two clicks away...

[JustSomeDude]

yes my iMac does detect the Samsung as a display but then thats about as far as it all goes. if i click on any lower res setting my mac blinks and changes but the tv sort of just sits there

You're setting you imac monitor instead of the samsung. If the "gather windows" doesn't bring up a second display preferences dialog, try changing the setting as they should be for the samsung (like you have been), and then turn on mirroring (click on the monitor icon in the menu bar to enable this). Once you get same display on both screens, you should then be able to click on the monitor icon and change the resolution for the imac.

Edit: just noticed:you only get the monitor icon in the menu bar if you have "show displays in menu bar" checked in the display preferences. Anyway, you can also turn on mirroring in the arrangement tab of the display preferences.

[ruk110]

rats ass-time machine didn't work so now i am completely baffled. it can only put it down to the leads or the tv. im gonna try and link the tv up to my mac mini tomorrow and see what happens...

[maxmiles]

rats ass-time machine didn't work so now i am completely baffled. it can only put it down to the leads or the tv. im gonna try and link the tv up to my mac mini tomorrow and see what happens...

Perfect, good troubleshooting. This way you'll be able to rule out at least one factor. But a defective adaptor is definitely is a possibility, (I suppose, I've never had these adaptors fail) so it would be good if you could get your hands on another and test it out.

[ruk110]

oh my gosch, i have found the fault. the Mini displayport to hdmi adaptor wire has to be DEAD straight in order to work.slightest movement takes the picture away and confuses my tv. Thanks guys for all your help :)

[maxmiles]

oh my gosch, i have found the fault. the Mini displayport to hdmi adaptor wire has to be DEAD straight in order to work.slightest movement takes the picture away and confuses my tv. Thanks guys for all your help :)

Ha! As usual it's the freakin' cable. I suppose that's included in the "check connections" step, but it gets me all the time too. Routinely I'll have to triple adjust the miniDVI-to-DVI adapter for this old Studio display I'm running. Glad you figured it out. Regards, max