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wjunium

macrumors newbie
Original poster
Jun 24, 2009
1
0
I have a Mac Pro with a ATI Radeon XT2600 HD video card. Attached is 1 30" Apple Cinema display. I am attempting to take the second DVI and with a DVI -> HDMI adapter, run to an HDMI switcher then to a 40" Sharp Aquos display.

The computer acts as though it is seeing both displays but the Sharp will not display my computer image.

What I have tried:
1. Direct from computer to display via HDMI = no signal
2. Reboot computer with only Sharp attached = signal from Mac until adjust any video settings
3. Unplug Cinema Display DVI with Sharp still plugged in = hit or miss display of computer to Sharp
4. Various other settings, etc.

I spent time on the phone with Apple and Sharp just to make sure I wasn't missing something. That didn't help one bit.

Any ideas? I am tempted to buy the Blackmagic HDMI card.

No, my Sharp doesn't have DVI in.

Thanks,
Warren
 
I have a Mac Pro with a ATI Radeon XT2600 HD video card. Attached is 1 30" Apple Cinema display. I am attempting to take the second DVI and with a DVI -> HDMI adapter, run to an HDMI switcher then to a 40" Sharp Aquos display.

The computer acts as though it is seeing both displays but the Sharp will not display my computer image.

What I have tried:
1. Direct from computer to display via HDMI = no signal
2. Reboot computer with only Sharp attached = signal from Mac until adjust any video settings
3. Unplug Cinema Display DVI with Sharp still plugged in = hit or miss display of computer to Sharp
4. Various other settings, etc.

I spent time on the phone with Apple and Sharp just to make sure I wasn't missing something. That didn't help one bit.

Any ideas? I am tempted to buy the Blackmagic HDMI card.

No, my Sharp doesn't have DVI in.

Thanks,
Warren

That's an odd one, I'd bet this is an incompatibly with the ATI card/OS X/and your Sharp in specific.

1. Read the Manual for the Display.
2. If that fails, check that the EDID is being picked up correctly.
3. Boot Windows(Boot Camp) or Linux(Boot camp) and see if you have this trouble.
4. If you still have this Trouble in Linux/Windows, Contact Sharp/ATI.

To check the EDID /Applications/Utilities/Terminal.app

Code:
ioreg -l -w0 | grep EDID

The output should look like this:

<00ffffffffffff00593a26000101010126220103083a20782a986ca3554498260e4749a54a0045590101010101010101010101010101662150b051001b304070360048804200001e000000fd0032551f460b000a202020202020000000ff00464d4241414833383336363533000000fc00565732364c20484454563130460069>

For each display, there are some Free tool for Windows, that can be used to check it there, if the display works O.K. in Windows/Linux, you can dump the EDID and Correct it in OS X.

Via, /System/Library/Displays/Overrides

Have a look at it, if you can't figure what I'm saying, just Boot Windows or Linux and Reply back, as to if the Display Works Correct or not.

If it does, I'll give you a Step by Step of How to fix it in OS X.

If not, it's up to Apple/Sharp/ATI as it's a ROM issue.
 
Cuda,

I am running my mac to a projector via HDMI. When I connect it directly everything is great. When I run HDMI through my receiver first, everything shows up green. I believe the problem is that the receiver isn't passing the EDID through correctly.

In your previous message you mentioned that there is a way to fix the overrides folder if I have the correct EDID. I can get the EDID by connecting the projector directly to the machine. Is there a way to then force OSX to use that EDID?
 
Has anyone experienced this problem?

I have a Mac Pro with the nvidia 8800 GT attached to a Sharp Aquos 32" 1080p display via HDMI->DVI-D as my primary display

Everything displays and operates perfectly well. But if I switch inputs to my Digital Cable Box and switch back, the mac can't recover and display an output. The Sharp doesn't register a display.

I have to force the power off on the mac pro and then re-power on.

The only way I can switch the input is to: shutdown the mac pro, switch inputs to another input then switch back then power the mac pro back on.
 
Hi all - and happy new year!


I have a related problem that I hope someone can offer some advice for.

We have a shiny new HDMI switching amp which switches between our PS3 and our Mac Mini. The Mini is connected to the amp with a DVI-HDMI cable.

The picture is beautiful - when it displays. Firing up the Mini with the amp set to that input results in a nice 720p display. However, it seems that the Mini is reverting to standard resolutions after a period of the amp either being off or set to the PS3 input. ScreenSharing into the Mini shows that it no longer has the option of displaying at 720p.

I can pull the EDID that it's using when working correctly via the Terminal. I'm thinking that what I need to do is force the Mini always to use this EDID or prevent it from sensing no HDMI devices somehow?

Any suggestions gratefully received!
 
Gravedigging...

Sorry for digging up this 1 year old thread, but I am also looking for a way to force EDID information to a Mac Mini so I can play multichannel audio through a HDMI Matrix.

Anyone know a way to do this?
 
You know, I never did find a way to do this. We just make sure the Mini sleeps when we switch the amp over, so that when we switch it back and wake the Mini up, it runs the detect video script again and alters the output.

There's an "HDMI detective" made by Gefen that claims to be able to save and force EDID settings - we didn't bother and YMMV etc...
 
HDMI Issue.

@Cuda

Mate, I need a little help and I believe you could help me with this HDMI issue I'm facing.
I own an Samsung BX2350 LED (HDMI + VGA inputs) and an GeForce 9800 GT (512 Mb DDR3 + 256 bits + DVI|VGA|HDMI outputs) but when I updated my OS X into 10.6.X I loose the capacity of changing resolutions.
I was reading your post and you said about EDID issues.
In 10.6 I can check it with the code you posted and the ioreg returns me this:
Code:
<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>
Is there any chance of using this IOREG info to make display works as it should in 10.6.X versions of OS X?
You told in the forum you could post an step-by-step solution for that and I think I can try your solutions since most of the solutions available for this kinda issue didn't worked for me.

I beg you for an answer.

Cheers,
bb.
 
Last edited:
Which Sharp display is it? I'm running a flashed 4870 and a 2600 together with the Sharp LC40E77UN (40" 1080p) LCD TV plugged in going DVI -> HDMI off of the 2600 and it works fine...with three other monitors going at the same time.

It's not the card or the mac, so it's very likely the specific display.
 
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