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So this update has fixed the bug

So it is confirmed then, that this bug is fixed.
At last, I can plug in my monitor again.
(My nice Apple keyboard is covered with dust now.)

I dont think I would praise Steve that much though.
This is stupid, obvious bug that shouldnt be there at the first place!
 
Running into the same issue here. After "upgrading" to 10.5.2 my MBP doesn't work in closed-lid mode with an external monitor - essentially the monitor goes to sleep and doesn't wake up.

I sure hope Apple is aware of this issue.

Yep - that's the issue alright - well documented in several threads. Apparently they do know about it - hopefully they FIX it in 5.3... so far the updates to Leopard have made my MBP LESS stable and more buggy, so much so that I've reverted to Tiger. Runs great. Really makes me think they released leopard before it was really ready. I do miss a couple features, but I sure don't miss the bugs.
 
EFI 1.5.1 solved that issue. I haven't done the Graphic Update, and am unsure about doing it.
 
So glad this is not just me. Mine has been all jacked up using my 1920x1200 external in clamshell. Same problems as described above. Hopefully this will get dealt with right away. I thought I was sitting pretty after updating the mini, so I did the laptop soon after.

I am afraid to even plug in my external now...

As I mentioned above: firmware 1.5.1 solved the monitor issue. If your notebook was updated to 1.5.1, then chances are the external monitor issue is resolved.

When it was not working, here is what I was doing to use my external monitor:
1- boot the notebook with the external monitor unplugged.
2- Once the desktop shows up, plug the monitor
3- the external monitor should work at the correct resolution!
4- if you want to only use the external monitor, close the notebook lid, let it go to sleep, then hit any key on the keyboard to wake up the notebook.

hope it helps!
 
Yes, it would appear that MacBook Pro EFI Firmware Update 1.5.1 resolved the issue with external displays as well as the wake-from-sleep blank screen issue caused due to the fact the machine was sending the output to the wrong device.
 
Yes, it would appear that MacBook Pro EFI Firmware Update 1.5.1 resolved the issue with external displays as well as the wake-from-sleep blank screen issue caused due to the fact the machine was sending the output to the wrong device.

So that is the cause of it? Sending output to the wrong device?
At last I know what is wrong!
Apple indeed did solve the problem, but it would really be nice if they also tell us what went wrong.
 
So that is the cause of it? Sending output to the wrong device?
At last I know what is wrong!
Apple indeed did solve the problem, but it would really be nice if they also tell us what went wrong.

indeed it would have been nice to know the source of the issue, but the most important part is that it is solved!!
 
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