Mac Pro (Early 2009) Not Recognizing Apple Display

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Mac Pro (Early 2009) Not Recognizing Apple Display

I have a Mac Pro (Early 2009) which I upgraded to OS X Yosemite a while back. At first I experienced some crazy display issues like flickering and snow. Now, it no longer recognizes my Apple Display at all.

I've read about a lot of similar issues with MacBook Pros not recognizing external displays, and the fix seems to be simple enough, requiring users to fiddle with the Display Preferences. A Mac Pro, however, only has an external display, so I can't use it at all.

I know the Apple Display is fine because, ironically, it works fine with my MacBook Pro. I can also access my Mac Pro over my LAN, but I when I try to open the Mac Pro's System Prefs, it opens the preferences on the MacBook. Also screen sharing is not currently enabled on the Mac Pro. I thought about buying Apple Remote Desktop, but I don't want to spend the money, and I think I would still need to access the Mac Pro to install the client software on it. I especially don't want to pay Apple $30 for a one time support ticket or have to schlep my tower to the nearest Apple store which happens to be in a mall.

Does anyone have any idea how I might go about solving this?

Thanks in advance for any help!

DG

Mac Pro

Posted on Mar 7, 2015 10:40 AM

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Answer 1

lllaass

Level 10

210,513 points

Mar 7, 2015 10:47 AM in response to dangerdes

How is the display connected to the MP?

Does that output on the MP work for other monitors?

What graphics card is installed?

Maybe a bad graphics card.

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Answer 2

dangerdes Author

Level 1

0 points

Mar 7, 2015 11:01 AM in response to lllaass

The display is connected to the MacPro via the mini displayport for video output and also via USB for extended connectivity, i.e. keyboard, etc., which BTW works through the display (I can push the eject button on the keyboard which is plugged into the display and the tray on the tower will open up).

The graphics setup is the original stock setup: - NVidia GeForce GT 120 512 MB

The port on the MP is not working with any other monitors. I used a mini displayport to HDMI to try a different interface, but no luck.

And I had no problems with the graphics card prior to upgrading to Yosemite.

I have, howerver, replaced the RAID card battery no less than three times.

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Answer 3

pmiles

Level 6

16,014 points

Mar 7, 2015 11:09 AM in response to dangerdes

If the display works when connected to another computer and doesn't when connected to the MacPro, it's the not the display.

If none of the display ports on your MacPro work with any other display, then it's the graphics card.

You could try resetting the PRAM/VRAM/SMC to see if that fixes it, but it sounds like you're going to need a new graphics card.

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Answer 4

The hatter

Level 9

61,031 points

Mar 7, 2015 11:14 AM in response to dangerdes

2009s came with an OEM GT120.

Upgrades over upgrades, eventually there is likely to be trouble. Do a clean install, keep the old system as is, your safety net while you test the waters and see if new OS is workable. Do a quick install of Yosemite or even Mavericks on another device.

Do a Safe Boot. Boot into Recovery Mode and check the condition of the system drive for repairs.

Clone the system so you have a backup and then erase and install either Yosemite or Mavericks.

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Answer 5

lllaass

Level 10

210,513 points

Mar 7, 2015 11:16 AM in response to dangerdes

First try resetting the SMC and NVRAM. When resetting the SMC depress and hold the Power button depressed for a couple of seconds with power cord disconnected

Intel-based Macs: Resetting the System Management Controller (SMC)

About NVRAM and PRAM

If you boot with the Option key depressed do you get anything on the screen? If not then that indicates a bad video card.

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