External Display Goes Black and Flickers with Macbook

i am having similar external monitor issues since the 10.6.3 upgrade, when i went to the apple store today to look at the ipad i asked an employee about it, he said they've heard of others having issues as well. i'm also having an issue with video in my browser, regardless of which browser i use, and i can not always replicate the issue, but each time it's the same, audio but no video. and i know it's not my connectivity, because i have tried it on several different networks. AND in itunes, i HAVE to use playback "in itunes window" option when i prefer the "in separate window" option otherwise i get the same audio but no video problem. apple has got to fix this, it's entirely unacceptable to have something like your monitor suddenly become unusable.

hoping i can use time machine to revert to 10.6.2 and solve this till there is a real fix.

Hi There same problem here, with Lg w2242s @1680x1050. Since the update it flashes image and stays all the time blank including going to sleep. Tried to apply the miniDP firmware update and it says that there isn't one connected!

I'm also having this same problem. I use an Acer x223W monitor @ 1680x1050. It generally works, but randomly flickers out about 4-5 times a day. It only started happening with 10.6.3.

My MacBook is older, I'm using the Apple mini-DVI to DVI adapter

After installing Mac OS X 10.6.3 is also my screen is with the recommended resolution (1680 x 1050). I have an LG W2242S screen via a Mini DisplayPort to VGA adapter connected to my Mac Mini.
Lower resolutions work but still do not look.

I even visited the local Apple Premium Reseller, but to no avail. This problem could hopefully be resolved in Mac OS X 10.6.4

Same problem here with my SyncMaster 2243lnx. On some German forums I found a hint, that SwitchResX should be able to solve the problem. But I did not give it a try yet, since I am still searching for a solution without any tool or third party hack.

This is happenning to me too. Tried plugging my Samsung 2253BW in with the miniDVI - VGA adapter (VGA into the monitor) and the screen flicks on for half a second, then goes black. Can't change resolution etc. since that monitor (the black one) is my primary display...

Please fix this Apple, it is annoying as ****.

I also have the same exact problem... I believe anyway.

I have my macbook pro charging, and connected to my TV using a MiniDP->HDMI adapter. When I wake it from sleep all you see is a blank screen with a mouse cursor. I have to reset it to get my screen back to normal.

I called apple support and they had no idea, so I went to an apple store and they got it to work with one of their TV sets... still had no help to offer for my personal set. They told me maybe the firmware for my TV was out of date. I don't understand! it works fine when the lid is open, why can't it work in clamshell mode?!?!?!?! if anyone finds out, PLEASE email me too! I will be searching as well.

Fixed. Using LG L204WT and 10.6.4.

1) Downloaded SwitchResX from http://www.madrau.com/.
2) I did not install the optional modules.
3) The default resolution for my L204WT was set to 1440x900. Changed this to 1680x1050. (This step might not be necessary.)
4) Under "Current Resolutions" SwitchResX listed 1680x1050 twice. One of them works! The other makes my display go black. It seems like OS X simply uses the wrong settings for my display.

The settings for each of both entries are listed in SwitchResX. I'll list the differences using "|" as a separator. "H" is horizontal, "V" is vertical.

Working settings | bad settings

Pixel clock: 146.25 | 119 MHz

Front porch H: 104 | 48 pixels

Sync width H: 176 | 32 pixels

Back porch H: 280 | 80 pixels
Back porch V: 30 | 21 lines

Blanking H: 560 | 160 pixels
Blanking V: 39 | 30 lines

Total H: 2240 | 1840 pixels
Total V: 1089 | 1080 lines

Scan rate H: 65.29 | 64.674 kHz
Scan rate V: 59.954 | 59.883 Hz

Positive sync. H: unchecked | checked
Positive sync. V: checked | unchecked

Does anyone know how to use the working settings without SwitchResX?

Message was edited by: Markus00000

Message was edited by: Markus00000

Message was edited by: Markus00000

Markus00000 wrote:
dutzi, can you run your external display at its native resolution when the internal display is off (lip closed)?

For me that's only working when both displays are on.

Thanks Markus00000 !

Same issue for me (same resolution for external screen as all of us in this thread). It will only work if both displays are on.

Also if I launch a fullscreen application with a separate video mode (e.g. a game), I can no longer set it to the working setting; It will only use the (broken) OSX default settings for this resolution.

Has anyone found a way to completely override the OSX settings (dual screen + clamshell + full screen app modes) ?

Thanks! Works fine for me, it even works in Clamshell mode and when playing games - at least for the Steam version of Portal, that's the only game I tried.

I did everything as you described, except for step 3, and also set the bad 1680x1050 setting to be redirected to the working one in the "active" column. Maybe that's what's needed to make it work with the lid closed?

I had this same problem. My primary screen was switched to the external monitor (LG L226WTQ) so my menu bar was gone when Apple did one of their magic upgrades. I installed the SwitchResX (per Markus00000's instructions below), ***BUT*** unlike in Markus's description, I did install the optional plugin for the Context menus. That adds a right-click option to your Finder menu so you can click on the desktop (of the visible screen) and then choose to mirror the monitors or something else to make the menu bar appear above both screens or just the visible one. Then you are free to make the changes to the display and change your laptop to the primary monitor again.

Also massive thanks to Markus00000 for posting the SwitchResX fix option. Saved me too. SwitchResX is shareware so you don't have to pay to test it, but I will definitely be registering this app (as anyone that has success with it should) and paying them the much earned $$ or in their case €€.

Message was edited by: Psychictoad

I installed the shareware version of SwitchREsX and it worked for me!
this problem was intermittent -and usually I could solve it switching to "Mirror Displays" and going back- but after a couple of months not using this external monitor (a Samsung 2243LNX) the issue happened and the monitor went black to never awake with 1680x1050 res -every other resolution worked fine for me)
In SwitchResX I put the monitor in 1689x1050, create a "Custom Resolution" that took some automatic values from the current resolution and after that I had two 1680x1050 resolutions in the Resolution List. In the Menu Bar Icon appears now 1680x1050 59,9 Hz... I don't know if the difference with the standard one (at 60Hz) could be the issue here.
In any case: It worked.
Hope this could be useful for others suffering this -really- annoying problem.

Hello,

I've been experiencing the exact same problem with my Samsung 223BW. Every other resolution works, except the 1680x1050. And all this is started after I upgraded to 10.6.3.