New 2012 iMac as external display for PC

[cosmicjoke]

Considering no one has a 2012 iMac, it is tough to say but you can upgrade the iMac with the Geforce GTX 680MX, which is a lower-clocked Geforce GTX 680.

Hard to get a faster single GPU today

While that's great and all for all in one gamers, there's still a place and reason people want towers w/ full blown beefy desktop gpus clocked at desktop speeds, not to mention OCing the CPU... Running some of these games at 1440p @ ultra settings and holding 60fps is no easy task, even w/ a full blown 680.

My only concern is that Thunderbolt technology might actually be a hindrance to gaming performance.... After all, using lucid virtu to copy the framebuffer of the discrete graphics card to the iGPU to output through the TB port has to translate into some performance loss, maybe enough to offset the gains of using a real GTX 680 over the mobility card... Not to mention I believe TB borrows like 4x lanes of your PCI-E... Ideally you'd use the outputs of the GTX 680 dual dvi/displayport to a traditional monitor and screw the Lucid Virtu. There are too many downsides to TB technology and Windows, including the lack of hotplugging, so you'd really need to have the iMac in target display mode on a cold boot with Windows each time you'd want to use your gaming PC.

 

[vooblu]

you'd really need to have the iMac in target display mode on a cold boot with Windows each time you'd want to use your gaming PC.

That's what I was thinking..

If I can manage to get everything working (in a few weeks time once my iMac comes), I'll report back with the correct setup steps and framerates with MVP, etc.

 

[hallee]

Did you change any settings in your BIOS so integrated graphics were set to default on the PC, etc? Some thunderbolt motherboards also restrict video output to the first thunderbolt port if there is a DVI-D monitor connected as a secondary display. From the manual: "When a monitor is connected to the DVI-D port, the MDP2 Thunderbolt port can support Thunderbolt storage device(s) only."

Did you also update the intel graphics drivers to the latest version before trying?

Just making sure all options were covered.

I tried all of these things, and both Thunderbolt ports.

But from recent posts, it seems that Windows 8 may fix the issues! I'll get Windows 8 today and install it, and let you know how it turns out. I really hope this works, I'd rather not have wasted the money on the new motherboard.

Just for reference, I do have the Gigabyte GA-Z77X UP4 TH.

I'll try everything I can.

 

[Mac32]

It seems thunderbolt for external graphics card is a dead end. I did some research on the Internet (read articles where thunderbolt controllers were tested with different graphics cards), and unless Apple/Intel makes some big upgrades to the thunderbolt standard, it's an expensive solution which will only give a midrange performance. A desktop Nvidia 680 card in an external thunderbolt enclosure would be a waste, the lack of bandwidth bottlenecks the performance rather severly - not to mention future generations of even more powerful graphics cards...

BTW: Could anyone do some more testing on Windows 7 again? It would be interesting to see if Windows 7 also works after all. I know another user reported his attempts were unsucessful, but it could have been a firmware issue with the motherboard, or a wrong setting in the bios...

 

[hallee]

A desktop Nvidia 680 card in an external thunderbolt enclosure would be a waste, the lack of bandwidth bottlenecks the performance rather severly - not to mention future generations of even more powerful graphics cards...

This isn't what we're talking about at all.

 

[vooblu]

But from recent posts, it seems that Windows 8 may fix the issues! I'll get Windows 8 today and install it, and let you know how it turns out.

Sounds good! I've ordered my iMac but it won't be coming until January. It may be the new Cactus Ridge TB controller in the new iMacs (I think the older gen used different controllers). Or as you said, it may be Windows 8.

This was added to the iMac spec page a few days ago (I think, since I hadn't seen it prior), which simply states that a thunderbolt cable is needed.. doesn't mention anything about Mac > Mac only.

Support for Target Display Mode via the Thunderbolt port using a Thunderbolt to Thunderbolt cable (sold separately)

 

[hallee]

This was added to the iMac spec page a few days ago (I think, since I hadn't seen it prior), which simply states that a thunderbolt cable is needed.. doesn't mention anything about Mac > Mac only.

The Apple support site has this to say: "iMac (21.5-inch, Mid 2011) and iMac (27-inch, Mid 2011) and later computers support Target Display Mode via Thunderbolt to Thunderbolt cable (2 m) when the source is another Thunderbolt-equipped computer."

So, it should work. I'm trying with Windows 8 right now and have no luck.

I think my problem may be that I'm using a rather outdated i5-2400 with HD Graphics 2000, as opposed to the new Ivy Bridge chips with HD Graphics 4000. I'm thinking maybe it's the onboard graphics that is stopping this from working.

 

[vooblu]

I think my problem may be that I'm using a rather outdated i5-2400 with HD Graphics 2000, as opposed to the new Ivy Bridge chips with HD Graphics 4000. I'm thinking maybe it's the onboard graphics that is stopping this from working.

For some reason I thought I had HD 4000, but I have a i5-3570 which only has 2500 (the i5-3570K has the 4000). If this is the cause, hopefully the 2500 graphics are compatible. The laptop which worked has 4000.

Did you try with Virtu MVP installed?

 

[hallee]

For some reason I thought I had HD 4000, but I have a i5-3570 which only has 2500 (the i5-3570K has the 4000). If this is the cause, hopefully the 2500 graphics are compatible. The laptop which worked has 4000.

Did you try with Virtu MVP installed?

2500 is in the same family as the 4000, so you should be fine.

And yes, Virtu MVP has been installed all along. However, it's really irrelevant whether it is; target display mode should work without it. MVP is just to improve game performance.

 

[Stuntmonkey]

Any news on this? I'm looking at a 27" iMac and will pass if this can't be done.

 

[vooblu]

Any news on this? I'm looking at a 27" iMac and will pass if this can't be done.

I ordered my iMac a couple of weeks ago - just waiting for it to be delivered in January. I plan on trying this until I'm completely out of ideas, so I'll reply back when I have some more news.

In the mean time, if anyone else has had some success like "sno1man" then please let us know. Hopefully we can find out what the actual requirements are (type of integrated graphics, if it only works on windows 8, if a 2012 iMac is required, etc).

 

[woodynet]

Hi everyone, I hope this isn't a dumb question, but I'm also looking at buying the 2012 21.5 iMac to replace my 2010 MacBook Pro, my work computer (That I own) is a Lenovo x220 with a display port, I'm going to buy a display port to mini display port cable and plug this into the iMac, will this work ? And if not is there a work around ? The other choice would be to keep the MacBook Pro for a bit longer (still runs fine) but buy a better monitor (like what's on the iMac)... Finding one is a bit difficult though. Thanks - woody

 

[vooblu]

my work computer is a Lenovo x220 with a display port, I'm going to buy a display port to mini display port cable and plug this into the iMac, will this work ? And if not is there a work around ?

The new iMac's only support video-in via thunderbolt cable (from thunderbolt > thunderbolt port). Since your laptop doesn't have a thunderbolt port, it's not possible to use the iMac as a screen for that laptop. No adapters exist at the moment.

 

[Petewood]

Hi everyone, I hope this isn't a dumb question, but I'm also looking at buying the 2012 21.5 iMac to replace my 2010 MacBook Pro, my work computer (That I own) is a Lenovo x220 with a display port, I'm going to buy a display port to mini display port cable and plug this into the iMac, will this work ? And if not is there a work around ? The other choice would be to keep the MacBook Pro for a bit longer (still runs fine) but buy a better monitor (like what's on the iMac)... Finding one is a bit difficult though. Thanks - woody

@woodynet - did you ever manage to get this working with mini display port? I also need to use the display with my Lenovo T410, but I have limited desk space for a second monitor. Many thanks.

 

[vooblu]

...

Hi,

My iMac arrived yesterday and I've been trying for 4-5 hours today trying to get it working as a monitor. I get the "ba-dum" noise in Windows when I connect the iMac, but that's all. Target Display Mode doesn't activate.

Do you have bootcamp installed on your iMac or was it a fresh installation when you tried it? I would love to know what drivers were installed. None were offered to me, so I don't think the PC recognizes the mac as a monitor.

hallee: When the iMac is connected, does it appear as "PCI to PCI Bridge" under "Devices and Printers > Unspecified" in Windows 7? That's what happens for me, but it's not recognized as a device/monitor (hopefully the drivers fix this if they're available somewhere). I'm starting to think that hd4000 graphics are needed.

 

[hallee]

Hi,
hallee: When the iMac is connected, does it appear as "PCI to PCI Bridge" under "Devices and Printers > Unspecified" in Windows 7? That's what happens for me, but it's not recognized as a device/monitor (hopefully the drivers fix this if they're available somewhere). I'm starting to think that hd4000 graphics are needed.

Yes, I get the same thing under Devices.
This news article from Gigabyte suggests that HD4000 are needed for their proprietary 4K output driver. I can only assume that something about the newer integrated graphics is more compatible with Thunderbolt. Unfortunately, I just can't justify spending money on a new CPU since it might not work, and even if it did get through to the iMac, there's no guarantee that Lucid MVP would work with the games I want to play.

 

[HurryKayne]

So,just HD4000 can drive Thunderbolt Imac...but what about the GPU output from the Gpu Card on that Thunderbolt Motherboard?Do we need Thunderbolt Gpu card or the signal passes from the Gpu through the mobo and out its Thunderbolt port to reach the Imac?
Seems complicated even to imagine..so i don't think this is the case..forgive my ignorance on this issue.

 

[hallee]

So,just HD4000 can drive Thunderbolt Imac...

I'm not sure that's even the case. Nobody's really tried any of this before, sadly. It's new ground, and I think it's more likely that it doesn't work.

 

[drambuie]

Asus has been working on a PCIe card called the ThunderboltEX. The requirements are a P8Z77 Asus motherboard with Thunderbolt output, and a display card with Displayport output. The Displayport output is looped to the Dsplayport input on the ThunderboltEX. The ThunderboltEX combines the motherboard's Thunderbolt signal with the display card's Displayport signal to produce Thunderbolt output with full discrete GPU performance. The motherboard's Thunderbolt output only uses the integrated Intel HD4000 GPU.

Here's an unboxing of the ThunderboltEX:

http://www.youtube.com/watch?v=4oEM7sRizvw

 

[HurryKayne]

Thats interesting,a little..complicated..but ,if it works,great.
If only Intel and Apple could make it less..hard.....

 

[hallee]

Here's an unboxing of the ThunderboltEX:

http://www.youtube.com/watch?v=4oEM7sRizvw

Keep in mind that this has been out for at least 6 months. In that time I haven't been able to find a single case of a PC outputting video to an iMac in Thunderbolt target display mode.

So again, I don't think it's possible.

 

[drambuie]

If this is the case, and a TB equipped PC can output to an Apple Thunderbolt display, it implies that there's a two way handshake going on between an iMac and a Thunderbolt connected computer, and if the other one doesn't identify itself as a Mac, then no dice.

 

[Mac32]

Keep in mind that this has been out for at least 6 months. In that time I haven't been able to find a single case of a PC outputting video to an iMac in Thunderbolt target display mode.

So again, I don't think it's possible.

It's possible, as a new iMac user confirmed on the previous page of this thread. I've also seen youtube videos where new motherboard technology is demonstrated, routing the discrete graphics card output via the motherboard and throught the thunderbolt connection.

 

[vooblu]

Unfortunately the one person who has achieved it doesn't actually own the laptop (it was his friends), so he hasn't posted the exact specs, what drivers were downloaded, etc.

I have spent dozens of hours reading up on this subject and received my iMac 3 days ago. After hours and hours of trying, I have been unable to use it as a screen for my PC using the thunderbolt ports on the motherboard. The PC recognises the iMac as a "PCI to PCI Bridge", not as a monitor. It makes the "ba-dum" sound when it's connected, but that's all it does. If anyone knows where to download drivers, or how to categorize a device as a monitor in Windows 7, that may be the solution - apart from that, I'm out of ideas.

I assume it works easier with the TB display since it would be recognized as a monitor under Windows.

 

[Mac32]

There have been reports here on this forum about an issue with some of the new iMacs, they don't work properly in external display mode (some had to return their late 2012 iMacs for a new unit because of this). Maybe this isn't the case here though...

PS: Maybe you have to change some settings in the bios? I would take a look there, and see if there's any bios settings that might affect the connection.