Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

Use late 2012 Thunderbolt iMac as external display for a Thunderbolt equipped PC.

I realize that there are many ways to play PC games on a mac (boot camp, virtual machine, crossover, etc) but for some titles, it's just not the same. Moreover and most importantly, I'm trying with all will to use my late 2012 iMac as a thunderbolt display with my existing keyboard and mouse for everything as I don't want two monitors, keyboards, etc. This is why I'm heavily considering building a PC with a Thunderbolt equipped motherboard (http://www.newegg.com/Product/Product.aspx?Item=N82E16813131853 for example) with hopes of using my iMac as a Thunderbolt display for it.


I've scoured the internet for a week trying to see if anyone has confirmed if this kind of stuff can be done and the vast response is "I don't know." I've contacted 3 motherboard manufacturers as well as Apple on the matter. While all of them can't confirm anything for obvious reasons, I did get two small glimpes of hope.


When asking an Apple Senior Tech whether or not the scenario of using my thunderbolt iMac as an external display for a Thunderbolt equipped PC, the key line I got out of him was "if the motherboard's thunderbolt port outputs video signal, the iMac is sitting there looking for said signal when hitting CMD-F2 (toggle target display mode) and should find it and subsequently activate target disk mode." For the most part, this sounds logical to me and makes sense in my opinion.


When speaking with the Asus Tech Support regarding the board listed above, I asked him to confirm whether or not the motherboard's Thunderbolt port outputs data and video signals or if it was purely meant for data. His initial response was that yes, it should. He then consulted the online manual for that board (located here http://dlcdnet.asus.com/pub/ASUS/mb/LGA1155/P8Z77-V_PRO_THUNDERBOLT/E7309_P8Z77- V_PRO_THUNDERBOLT.pdf) to see if he can confirm it. Under the "Specifications Summary" on page X, it states:


Integrated Graphics Processor- Intel® HD Graphics support Multi-VGA output support: Thunderbolt/HDMI/DVI-D/RGB port Supports Thunderbolt with max. resolution 2560 x 1600@60Hz Supports HDMI with max. resolution of 1920 x 1200@ 60Hz Supports DVI-D with max. resolution 1920 x 1200@60Hz Supports RGB with max. resolution 2048 x 1536@75Hz Supports Intel® InTruTM 3D/Quick Sync Video/Clear Video HD Technology/InsiderTM


I'm reading this as "Thunderbolt port supports Thunderbolt with max resolution of 2560 x 1600 @ 60Hz," which convinced to the Asus tech and highly suggests to me that this Thunderbolt port does in fact output full screen native resolution iMac-via-Thunderbolt video.


Furthermore, if you go to the motherboard's official product page (located at http://usa.asus.com/Motherboards/Intel_Socket_1155/P8Z77V_PROTHUNDERBOLT/#overvi ew), the first section is regarding Thunderbolt. It states "An industry first, ASUS has placed Thunderbolt I/O technology onboard, and are set to revolutionize the speed at which peripherals and displays operate." It then says "For example, users can connect multiple native Thunderbolt storage devices, an HD video capture device and even an HD display to a single Thunderbolt chain while maintaining maximum throughput." Finally, it states "For a list of certified Thunderbolt products, please visit: https://thunderbolttechnology.net/products." If you go to this link and sort by "Computer" and "Apple," the first result is the (my) iMac.


To me, this is all evidence pointing towards to the direction of attaining my end goal. Do you agree? Can you think of any reasoning as to why this won't work? The biggest issue here is that in order to test this, I have to buy the non-refundable motherboard along with a non-refundable CPU, outfit it with a decent cooling system, maybe even a case, and the rest later on if confirmed...which kind of *****. Any thoughts at all would be very helpful as I know I'm not the only one with the question but am probably one of the few so married to the idea of making this actually work.

iMac (27-inch, Late 2012), OS X Mountain Lion (10.8.2), 3.4GHz Intel Core i7, 16GB RAM

Posted on Apr 20, 2013 9:42 AM

Reply
8 replies

Apr 20, 2013 11:18 AM in response to Zathrak

I also just found the manual for another Thunderbolt equipped motherboard, in this case it's the "MSI Z77A-G45 Thunderbolt LGA 1155 Intel Z77 HDMI SATA 6Gb/s USB 3.0 ATX Intel Motherboard with UEFI BIOS" which you can find at http://us.msi.com/service/download/manual-19309.html. On page 1-4, it states: 1x Thunderbolt port** (Mini DisplayPort), supporting a maximum resolution of 2560x1600 @ 60Hz.


This also suggests that the video signal should be compatible to me. Though I did think of something...Mini DisplayPort and Thunderbolt both support the 2560x1600 resolution I believe. So, is it possible that these specifications on these boards might suggest that it would work with Mini DisplayPort (and therefore NOT Thunderbolt)?

Apr 22, 2013 8:03 AM in response to Zathrak

Well, according to another Apple Senior Tech, they looked in to it and stated that the firmware on the LATEST (Late 2012) iMac will not allow this to happen. Even if the motherboard is compatible and is broadcasting video, the iMac will not allow the signal to be compatible with the iMac. It's almost as if Apple figured someone like me would try and do something like this and figured, "nahhh...let's make him buy an additional cinema display or something."


Anyhow, back to the drawing board I guess. It just doesn't make sense to have a 27in iMac/Display sitting on my desk but not be able to use it as an external monitor for other various devices. Having two 27in displays sitting next to eachother is excessive for something like this. Frankly, having a second display of any size just doesn't make practical sense with the 27in iMac there. This is why I'm so ****-bent on finding a way to get native Windows (non-boot camp) on my iMac display that can handle things like modern PC Games like Battlefield 3, etc.

Apr 24, 2013 7:21 PM in response to Zathrak

Ahhhh! This is so frustrating! Why wouldn't they let us do that?! It just seems like a feature few would use so it wouldn't really hurt anyone but certainly inspire good faith in the customers.


You can connect an Air through thunderbolt without a problem, so there HAS to be someway to trick it to work with a PC as well. Maybe someone could hack the driver or something....

Use late 2012 Thunderbolt iMac as external display for a Thunderbolt equipped PC.

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple ID.