ThunderBolt + External Monitor = Mounds of Woe

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ThunderBolt + External Monitor = Mounds of Woe

I posted this issue in another thread but since I'm seeing more issues I thought it best to create my own post.

I use an external monitor, connected using either HDMI or DVI. This monitor (an Ausus) works fine & has been working correctly attached to my old macbook.

With the new 2011 MBP, I can get the external monitor to work, but it exhibits strange behavior. It's difficult to make it the primary monitor using the normal macbook methods, and so I have resorted to just dimming my MBP display to zero (which I don't like having to do).

Once the external is running (either mirrored or as extended) it functions normally. However if the MBP display goes to sleep (or the MBP itself goes to sleep), the external will go black but remain on. When this happens I can no longer turn the external on/off or use any of the buttons on the display. It's frozen in this black "on" state. I have to remove the mini display adapter from the Thunderbolt port which makes the MBP screen primary again & I can then enter pass and wake the MBP up.

At first I thought I could turn the external off and access the controls once the mini display adapter was removed but this is no longer the case. Once it's in this "frozen" state the external won't do ANYTHING until I actually unplug the power cord.

This renders an external monitor on the new MBP's unusable. I reported this to Apple directly along with this post. I may call apple tech support when i have the time. Hopefully I won't have to return this lappie because overall I really like it, but no external monitor is not cool.

I would love to hear if anyone else is having this issue or has any ideas for a fix.

13" macbook pro (early 2011), Mac OS X (10.6.6)

Posted on Mar 7, 2011 5:42 PM

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Answer 1

entropic23 Author

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Mar 10, 2011 11:14 PM in response to entropic23

I ended up having an involved session with apple tech support yesterday. I wasn't going to post anything here until I heard back from the apple engineers, but the gist of the situation is that DVI doesn't work reliably whilst using Thunderbolt.

While I was on the phone with tech, we tested two different setups (mini display -> DVI/DVI along with mini display -> DVI/HDMI) on three different monitors. Since my mini display adapter was DVI it made absolutely no difference whether or not I used a DVI/DVI cable or a DVI/HDMI cable.

Today I got a mini display -> HDMI adapter and have used it on my monitor with an HDMI/HDMI cable and everything works exactly as it should. I can finally work on an external display without hassle.

Tech support had me send some specific logs to apple engineers & I expect to hear back from Zach (apple tech) tomorrow or Monday and will update this topic then.

So while it's not a good thing that DVI is sketchy when using Thunderbolt, at least there's a very easy workaround for now ( if your monitor has HDMI).

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Answer 2

Mar 11, 2011 9:37 AM in response to entropic23

I just purchased a 13" 2011 MBP. Came home all happy and took my Moshi MDP to HDMI adapter, plugged in an HDMI to DVI cable to my 23" DELL P2311H monitor only to find that it says that the output frequency is wrong and I should set it to 1920X1080@60Hz, which is what my MBP was set at. Got another HDMI to DVI cable and this time nothing happened at all. The MBP detects to the monitor but nothing shows up on the monitor.

My P2311H has no HDMI input 😟 and I just bought it. I can confirm when I plugged in my Samsung HDTV using an HDMI to HDMI cable with my adapter and my MBP, it worked flawlessly.

I will call Apple as well and see what happens.

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Answer 3

entropic23 Author

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Mar 11, 2011 10:03 AM in response to gonzoguy24

Post back and let me know what tech says. When I spoke to them a couple days ago, both techs said this wasn't a rampant issue, but there are a lot of posts popping up so I have a feeling they're well aware of the situation now.

As far as I can tell using DVI anywhere in the chain results in sketchiness, so the only "solution" is to use HDMI... Or test a number of different DVI monitors to see if one works. As I said I tested on three monitors (using DVI) and none of them worked perfectly so it's a major crap-shoot.

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Answer 4

Mar 14, 2011 3:13 PM in response to entropic23

Not sure if Apple Tech got the message clearly enough yet, as the particular support person I talked to consider the problem "resolved" when mentioned that VGA does work (of course, DVI is still broken, which is the reason for calling them in the first place).

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Answer 5

Mar 16, 2011 3:05 AM in response to entropic23

Same Issue. Apple branded adapter with Dell Monitor. Computer does not realise that there is a monitor attached.

Pretty please fix it Apple.

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Answer 6

wind1084

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Mar 16, 2011 3:23 AM in response to entropic23

Same issue.
I have a Benq G2200HD monitor and it works well with my old Macbook on with DVI adapter.
I bought my new 13 inch macbook pro last week and it was working.
Today, when I replug the miniDP to DVI adapter, it won't detect the display anymore. I am sure that my monitor, cable, adapters are working.

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Answer 7

M Gnu

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Mar 16, 2011 6:05 AM in response to entropic23

I would not say HDMI is trouble free either.

Problem: New 13" MBP i7, connected to ASUS VE276Q via mini-display port to HDMI converter. Display sleep causes the ASUS to go to sleep (orange LED), then power cycle on after about 1 second. After the computer sleep timer threshold is hit, this behaviour continues, and MBP won't sleep until you touch the trackpad (internal or bluetooth).

Solution: MBP & ASUS behaves and sleeps the way it should when connected to this monitor via mini-display port to display port cable.

Also Another Solution: MBP & older ASUS VE22 series will both sleep correctly using the previously buggy MDP to HDMI converter.

Conclusion: MBP & some monitors don't work well together.

Sorry, not more scientific.....

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Answer 8

Mar 16, 2011 10:52 AM in response to entropic23

Just a note and I know it goes to a different crowd of people outside of those with 13 inch models. But the Thunderbolt + DVI combo on my new 2011 (17inch). Required me to have the discrete GPU enabled before it would detect. So if any of you with 15/17's are running something like gfxCardStatus and locking down to only integrated GPU for power savings make sure to enable dynamic switching again if you goto multi-display setup.

Forgive me if this has already been stated in other threads etc.

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Answer 9

entropic23 Author

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Mar 16, 2011 5:26 PM in response to entropic23

I will be running a couple different tests for tech today and I will be sending the logs back to them today as well. At least the engineers are involved... So far I've run 3 different apple diagnostic apps, so my guess is that they're well aware of this issue... I will post back when I hear any news.

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Answer 10

Wyseman

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Mar 17, 2011 12:00 AM in response to entropic23

I have a similar issue here with an ASUS VK266H and a 15" 2011 MBP.
Tried the Apple branded Mini-Display-Port to DVI adapter and external monitor won't sleep, it just goes black but remains powered on. Apart from that, no problems with the display, works great.
I tried with a Toshiba monitor via DVI adapter and it worked just fine, powered off when it should.

I picked up a Moshi MDP to HDMI adapter (Asus Monitor has DVI, HDMI and VGA), but this has the same problem, no sleep, just black.

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Answer 11

Mar 17, 2011 9:45 AM in response to Wyseman

I also had a similar problem. When I attached my new 15" 2011 MBP to my dell sp2309W,
the computer screen went black and the monitor indicated there was no DVI signal.

The monitor had worked perfectly for two years with my old MBP 2007... so I figured it wasn't the monitor.

So I went back to the apple store and exchanged the Apple Branded Min-Display-Port to DVI adapter
for a new one and the problem was solved. I've been using it intensively for a week and a half
and so far there haven't been any additional problems.
Fingers crossed I just got a bad adapter.

I don't know if this will work for anyone else, but it worked for me. Worth trying if nothing else
is working.

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Answer 12

Mar 18, 2011 12:53 AM in response to George Waxstetter

I don't use a DVI oder HDMI Adapter. I've just a normal Mini-Display-Port to Mini-Display-Port-Cable. But the same problems.

Anyone else?

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Answer 13

entropic23 Author

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Mar 18, 2011 6:34 AM in response to blabla123

Yipes! No I haven't read about anyone with MDP to MDP issues. In fact the tech I spoke to said this setup was the most likely to have NO issues, with MDP -> HDMI following closely behind. You don't give any details, but are you sure your display is working correctly, namely its MDP? Meaning can you connect your old MBP (or whatever) from its MDP to the display MDP (rather than VGA etc)?

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Answer 14

Mar 18, 2011 11:28 AM in response to entropic23

My temporary workaround is to disable "Automatic Graphics Switching" and let the machine run on the Radaeon all the time since it's plugged to a power outlet anyway.

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Answer 15

Mar 19, 2011 6:12 AM in response to matthewadams

I thought this worked but today it didnt. So forget that idea.

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