Macbook Pro suddenly getting "Mode Not Supported" on HDTV?

[macumer]

Hi All.

Newbie on this forum!

Im having an issue connecting my Macbook Pro 15" i7 2010, to my Samsung HDTV. Up until last week, it was working fine. I connected it via a MiniDisplay Port to HDMI. I used to just plug and play!

I vageuly remember I either put laptop on standby or shutdown whilst it was connected to TV, and then unplugged it, and am guessing it somehow messed up settings to show its still connected to TV after I powered it back on.

But ever since, everytime I connect to my TV now, screen is either blank, or says "Mode Not Supported", or even says "No Signal". ??

Please help!!

 

[Detrius]

You should repair your permissions. You do this by restarting the machine and holding down command-option-R-P.

Just kidding. That's a PRAM reset. But a PRAM reset is really what you should do.

 

[macumer]

Thanks. But this did not solve the issue. Still get the same error. I get "No Signal" more often than "Mode not supported" now. When I fiddle with the cable, it switches between the 2 errors. Could the cable be faulty?

Im not sure because everytime i insert the minidisplay port into my MBP, screen flashes blue and I can open up the Samsung display properties window.

very strange?

 

[Detrius]

Seriously? Resetting the PRAM didn't fix it?

There in the Displays section of System Preferences, there's a "Detect Displays" button. Try that, then try changing the resolution of the second monitor (your TV). If none of this works, try connecting to the TV via DVI instead of HDMI (if possible) or vice-versa, or try a different cable.

You can verify your own cable by connecting the laptop to another TV/Monitor via that cable.

 

[macumer]

Yeah, It didnt fix it unfortunately! I actually tried every option I can try; including hitting "Detect Displays" many times, all the possible resolutions one by one...etc. But I dont think it would have helped even though the TV doesnt detect any signal coming through, which is very strange as the laptop does?

Only thing I can test is connecting laptop to another HDTV, but I only have 1 at home so may need to go to a friends house to try.

Im afraid I only have 1 cable, do not have a DVI cable.

 

[macumer]

Solved

Hi All,

Just an update. I went to the apple store to get it checked, and the guy tested it with their HDTV with their own MiniDisplay port cable.

They told me that it was receiving a connection but wasn't outputting, and that means the port on the hardware itself needs changing.

Since my DVD Optical drive was messed up, they said I needed a complete systemboard replacement, which they did in 3 days! And voila, it works again.

Thanks for the help though guys.

 

[cpaulPHL]

fix for "mode not supported" HDMI out

Hello - just went through this today on my brand new 2011 MacBook Pro i7 and Samsung HDTV via HDMI.

The issue is with the "integrated graphics" which doesn't output via HDMI/miniDisplayPort.

You need to go to the "Energy Saver" control panel, and turn off "Automatic Graphics Switching" which forces the high-performance graphics card.

Don't forget to turn this option back off, or you'll wonder why your battery isn't lasting as long!

Good luck,
- Paul