Use my iMac 27" all-in-one pc as monitor

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36 points

Use my iMac 27" all-in-one pc as monitor

I have a Windows pc with a DVI out connector and would like to connect to my iMac as a monitor occasionally. It requires an adaptor of mini displayport connector <-> DVI connector. Is it a open standard or Apple proprietary standard that I have to buy from Apple?

How can I switch from iMac pc mode to monitor mode?

When I use iMac in monitor mode, will the iMac pc mode switch off or go into standby?

iMac 27", Mac OS X (10.6.2)

Posted on Jan 1, 2010 9:53 PM

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Answer 1

Jan 1, 2010 10:05 PM in response to Ray Li1

It uses Mini DisplayPort, which is now an open standard. You can also convert from regular DisplayPort to Mini DisplayPort, with a simple cable, and DisplayPort is an open standard. There are graphics cards that output DisplayPort.

From DVI, it is not so simple. There are devices like this one

http://www.atlona.com/Atlona-DVI-to-Mini-DisplayPort-Converter-p-17859.html

but if you read the description carefully, there is a severe limitation when using it with a 27-inch iMac. Also, it is pretty costly. But the point here is, it's not a simple matter of changing the shape of the connector.

How can I switch from iMac pc mode to monitor mode?

The iMac is running, even when the display is being used by another computer or device. Command-F2 is the toggle.

When I use iMac in monitor mode, will the iMac pc mode switch off or go into standby?

I don't know what you mean by "iMac PC mode."

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Answer 2

Ray Li1 Author

Level 1

36 points

Jan 2, 2010 2:07 AM in response to Kenichi Watanabe

I do not understand Atlona's adapter for Mini Displayport connector to DVI connector is so complicated and expensive. The Apple one is just $29.

When I use iMac in monitor mode, will the iMac pc mode switch off or go into standby? It means when my iMac works as a monitor with external pc, what is the status of iMac internal pc, i.e., CPU, hard disk, graphic card, etc. Are they going into sleep mode or just idle?

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Answer 3

Ray Li1 Author

Level 1

36 points

Jan 2, 2010 2:31 AM in response to Ray Li1

Just read the UG and understand that the mini Displayport is able to output the signal to other monitor and input from other pc. Is my understanding correct as I would like to connect a pc with DVI video output to the mini Displayport of my iMac that acts as a monitor? Is command + F2 switched for internal or external monitor and input or output?

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Answer 4

Jan 2, 2010 2:44 AM in response to Ray Li1

Apple's adapter is only for video output. Mini DisplayPort to DVI. It does not work for converting video input.

"iMac PC mode"? Are you talking about using Boot Camp?

It is called +Target Display Mode+ when the iMac is working as a display. When in +Target Display Mode+, the iMac is still running. You can have it doing work, such as downloading files or acting as a server or whatever.

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Answer 5

Jan 2, 2010 2:47 AM in response to Ray Li1

As already mentioned, the video input must be from a Mini DisplayPort or regular DisplayPort. You cannot use Apple's $29 adapter to convert video input. That adapter is only for converting video output.

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Answer 6

Ray Li1 Author

Level 1

36 points

Jan 2, 2010 7:16 AM in response to Kenichi Watanabe

As the Apple adapter does not mention to convert video output only. In normal, it can work in reverse way. If you are right, thanks for your helpful advice as I nearly place the order to Apple.

The UG states that

Mini DisplayPort

Output port with support for DVI, VGA, and dual-link DVI. The 27-inch model also supports input from external DisplayPort sources. Required cables and adapters are available separately.

My iMac is 27" all-in-one unit. Thus I believe I can use the great screen as a monitor. I never thought to output the video to other monitor as 27" screen is the largest monitor at home. It is a desktop pc and I cannot carry it for presentation by connecting to a projector.

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Answer 7

Jan 2, 2010 11:51 AM in response to Ray Li1

Thus I believe I can use the great screen as a monitor.

Yes, of course you can use the 27-inch iMac as a display for another computer or device. However, the input must be Mini DisplayPort or DisplayPort.

You can convert DVI to VGA with a simple adapter. However, you cannot reverse that connection and convert VGA to DVI. That adapter's description probably does not say +for output only+ either.

Well, you can convert from Mini DisplayPort to DVI with a simple adapter. However, you cannot reverse that connection and convert DVI to Mini DisplayPort with that same adapter. It's not just a matter of changing the shape of the connector.

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Answer 8

Jan 3, 2010 10:08 AM in response to Kenichi Watanabe

Suppose I have a DVI output (1920 x 1200) that I'd like to input to the 27" iMac - what are my choices / chances?

What other resolutions does the iMac display support when in Target Display Mode? Is there a data sheet on this somewhere that I can read?

Thanks.

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Answer 9

Jan 3, 2010 11:56 AM in response to Jonathan Mortimer

There would have to be a special adapter that converts a DVI signal to Mini DisplayPort. I linked to such a product above; there may be others.

However, the 2560x1440 resolution of the 27-inch display is in the dual-link DVI range. If you read the description of that product, it says the output is only single-link so the best you can do is 1280x720.

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Answer 10

Feb 2, 2010 4:44 AM in response to Kenichi Watanabe

Looks like they feel your pain:

http://www.atlona.com/Atlona-Dual-Link-DVI-to-Mini-DisplayPort-Converter-USB-Pow ered-p-17922.html

It's 200 bucks, and says it's "27 inch iMac compatible".

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