I'm guessing because a device earlier in the chain might disrupt the signal. It probably isn't supposed to, but with electrons running there is always the possibility of interference of some kind.
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Apple Thunderbolt Display with Multiple Monitors: No Daisy Chaining Mini DisplayPort Monitors
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I'm guessing because a device earlier in the chain might disrupt the signal. It probably isn't supposed to, but with electrons running there is always the possibility of interference of some kind.
Why are people pissed off? You can run two 27" monitors off the 13" Macbook Pro. That wasn't option before this announcement. Everything else we knew for weeks if not months.
And are people really pissed off that old technology does not work with new technology? That just the nature of the beast. Besides, when have we been able to run dual monitors off a laptop that is officially supported by the manufacturer?
I love the sense of entitlement people have.
And are people really pissed off that old technology does not work with new technology? That just the nature of the beast. Besides, when have we been able to run dual monitors off a laptop that is officially supported by the manufacturer?
I love the sense of entitlement people have.
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When apple first anounced the tb acd, i understood that only the 2011 15" and 17" pro's would support dual tb acd.
Having the 13" pro also support 2 tb display, is just bonus. Had I had a requirement for dual acd support , I would have got a 15" pro".
When apple first anounced the tb acd, i understood that only the 2011 15" and 17" pro's would support dual tb acd.
Having the 13" pro also support 2 tb display, is just bonus. Had I had a requirement for dual acd support , I would have got a 15" pro".
That can't be the case. It's DisplayPort 1.2 that added those daisychain abilities, but:
-In Intel's original Thunderbolt tech brief (no longer available) they stated that Thunderbolt only supported DisplayPort 1.1a
-The Intel HD 3000 GPU only supports DisplayPort 1.1a (source). This is the only GPU in the MBP 13-inch, yet it does support 2 TB displays.
The first point no longer seems to be mentioned in the specs, so it might be that Intel has back-pedalled from this somewhat. But the latter point is definitely the case; HD3000 hardware is limited to outputting a DP1.1a signal.
Conclusion: in the current implementation, daisy-chaining Thunderbolt displays is a function of Thunderbolt, and does not depend on some underlying DP1.2 chaining support.
Classic Apple.
Apple doesn't play the backward compatibility game too much. If it takes extra work to keep a few people happy, they have no problem cutting the cord. I am not saying Apple is good or bad. It is just their mode of operation.
This is an excellent question. I'm quite curious about the answer. It could confirm some hypotheses I have for why chaining a DisplayPort display off of the Thunderbolt display doesn't work.
This is likely due to a firmware / hardware incompatability
I agree however remember display port is prior to thunderbolt. Those displays probably do not have the hardware and or firmware to support being daisy changed to a thunderbolt port. Yes the ports are technically the same in the look but not the hardware / firmware driving those ports.
So the question is could a firmware update solve this or dose the hardware chips on the display simply not allow for it? My guess would be its technically not possible due to hardware.
I agree however remember display port is prior to thunderbolt. Those displays probably do not have the hardware and or firmware to support being daisy changed to a thunderbolt port. Yes the ports are technically the same in the look but not the hardware / firmware driving those ports.
So the question is could a firmware update solve this or dose the hardware chips on the display simply not allow for it? My guess would be its technically not possible due to hardware.
the magic is slipping away....
One more bit of "magic" about TBolt just slipped away.
It seems to morphing from a "magical interface" to a "PITA interface" with each bit of news. And much of the PITA comes from trying to send both DisplayPort and PCIe down the same cable - I hope that TBolt 2.0 fixes that mistake.
One more bit of "magic" about TBolt just slipped away.
It seems to morphing from a "magical interface" to a "PITA interface" with each bit of news. And much of the PITA comes from trying to send both DisplayPort and PCIe down the same cable - I hope that TBolt 2.0 fixes that mistake.
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Well, welcome to portable computers, and the caveats that come with them. Maybe you should search for more issues, there are likely to be some.
Another example, many laptops have had low power Firewire or USB ports, that cannot power some devices, whereas a desktop can.
When the new ones come one just go to an Apple Store and tell them your situation and they will more than likely return it for you. Especially if you return it and you plan on buying 2 of them.
Here are the answers to your prayers
This company VillageTronic is making external desktop graphics card enclosures compatible with thunderbolt. AFAIK The external graphics cards would only have influence over external monitors (so no gaming on the internal for eg.)http://www.facebook.com/topic.php?topic=17873&uid=89321949134
can't wait to get this and have desktop class gaming on a laptop
It's not surprising at all that the laptops have a limit to many pixels they can drive. Two 27 inch displays is actually really great for a laptop and even surprising. But if the Thunderbolt system can't daisy chain and if that is true when mirroring rather than adding more desktop, then it's not meeting the Thunderbolt spec.
Has someone tried daisy chaining Thunderbolt to DP in mirroring mode?
Has someone tried daisy chaining Thunderbolt to DP in mirroring mode?
Here are the answers to your prayers
http://www.facebook.com/topic.php?topic=17873&uid=89321949134
can't wait to get this and have desktop class gaming on a laptop
Sonnet is also making a PCIe expansion box - it can hold a full length double-width card, and has the 75w PCIe supplemental power cable (150w total). There's also a half-length version.
http://www.sonnettech.com/product/thunderbolt/index.html (click the "Expansion" tab.
They also have a rack-mount TBolt chassis for a mini on the same page....
apple
I didn't know that, thanks for explaining it. I am not in that situation, but I would be pretty ticked if I was. I currently use an old dell and I was wanting to purchase a macbook air (whatever version is out late next year) and connect two of those 27 inch displays to it. I guess I'll have to wait and see what next year brings, hopefully this wont even be an issue.
Do you guys think that some 3rd party vendor will be able to make a product to allow for this, whether it be hardware or software based?
I didn't know that, thanks for explaining it. I am not in that situation, but I would be pretty ticked if I was. I currently use an old dell and I was wanting to purchase a macbook air (whatever version is out late next year) and connect two of those 27 inch displays to it. I guess I'll have to wait and see what next year brings, hopefully this wont even be an issue.
Do you guys think that some 3rd party vendor will be able to make a product to allow for this, whether it be hardware or software based?
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Good source. I think it has to do with the embedded displayport. I understand it doesn't say 1.2 or whatever, but if you look into what embedded displayport is, it supports 1.2 back in May 2010.
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Then again, I might've misunderstood that. Who knows...
...And it's Apple's fault:
"Q: Can an existing DisplayPort device (deployed today) be field-upgraded to enable the future feature 'daisy-chaining'? If so, how?
A: DisplayPort v1.1a displays are fully compatible with DisplayPort v1.2 PCs and graphics cards. A DisplayPort v1.1a display can be the last display in a DP v1.2 chain.
Here’s an example:
A PC with one DP connector is driving two monitors via daisy chaining. The 1st monitor is a DP v1.2 monitor with input and output connectors. The 2nd monitor is a DP v1.1a monitor. DP v1.2 PC---> DP v1.2 monitor with in & out connectors---->DP v.1.1a monitor."
http://www.displayport.org/consumer/?q=content/faq
If DisplayPort 1.2 can have the 1.1 display at the end, then my argument and phairphan's argument are mute. It must be Thunderbolt tech running the daisy-chaining (It makes since, it has to control the DP data and PCI data being set). Apple can't blame DP tech (not saying they did), they just didn't want to put that much work into it.
What are you talking about no longer available ??
http://www.intel.com/technology/io/thunderbolt/index.htm
Right there on right hand side. Search in the document for 1.1a.
"... 1 or 2 of which can be high resolution DisplayPort v1.1a displays ( depending upon the controller configuration in the host PC ) ... "
There has always been two factors. One, that the host PC's GPU can put out two DP streams to the TB controller. Second, that the TB controller had two internal input pins to accept the two streams. Either one of those two missing and you don't get two.
The multi monitor routing was something that the Thunderbolt protocol layered on top of DP traffic. It was not a v1.2 implementation. In fact, because TB has to do its own routing, v1.2 traffic is going to be harder for TB to route since it will need to untangle and send the right data to the right places.
That is prefectly fine for Apple since TB only supports 1.1a also.
P.S. The new Thunderbolt website has the exact same info
"...., 1 or 2 of which can be high-resolution DisplayPort v1.1a displays (depending on the controller configuration in the host PC). ... "
https://thunderbolttechnology.net/tech/how-it-works
TB doesn't do PCI-e v3.0 either. It is a technology for picking up and encapsulating legacy protocols, aggregating them, and sending them down a relatively short daisy chain. It is always going to be a bit being the bleeding edge in what is transported.
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TB works for the most part. What it is not living up to is the "Going to cure world hunger and be the one port to rule them all". That always was garbage and marketing kool-aid. Nothing does "everything".
I suspect part of the DP stream problem at the end of the chain is determining where the DP traffic can go. If hook to the TB/DP port on a host PC then it is relatively clear who is talking to whom. Likewise if have DP-less devices they know that the DP traffic is not for them because those controllers have nothing hooked to the DP pins internally. "Can't be for me, chuck this back to the host PC".
Depending on how the native DP "hello who is there" protocol works in conjunction with the "hellow who is htere" TB protocol there may be glitches in certain network configs as push out into the chain.
Shades of SCSI termination issues. SCSI worked very well... just was a bit quirky in some small areas.
I think he probalby refering to the "one and only one" menu bar of the Mac OS X implementation. Windows attaches menu bars to the window. So if you have a window totally to the right on your dual 30" set-up, you won't have to throw the mouse cursor a long distance to get to the File > Duplicate menu.
There are upsides and downsides with this. This has been debated on these forums before. Looks like going to get another round. However, "right mouse" / context sensitive menus can limit the need to travel long distances in many situations.
It is not a comment about can easily merge and arrange multiple displays into a single big desktop.
There are some interesting things on the Windows side too. Windows 8 in "full screen mode" will put the legacy windows desktop on the other monitor. Apple just blanks it out with a sea of "nothing". Some people will like that. Others won't.
Are you serious? I have a new TB MBP and a MDP ACD that I just got in may. Apple you blow. Maybe I should cancel my order.
I'm hoping third party products come to the rescue here. The only thing compelling about this monitor is that it gives you the equivalent of a docking station. If I can't connect my 30" Dell U3011 to this, I have no interest in it.
I wasn't really planning on getting this Thunderbolt display anyway, so I'm not particularly disappointed by this (as long as third party TB docks that support DisplayPort show up), but am a bit surprised they didn't make this work when clearly it should be possible.
I wasn't really planning on getting this Thunderbolt display anyway, so I'm not particularly disappointed by this (as long as third party TB docks that support DisplayPort show up), but am a bit surprised they didn't make this work when clearly it should be possible.
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