M7649 Display Won't Work on G4 Quicksilver

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Level 1

35 points

M7649 Display Won't Work on G4 Quicksilver

I have a G4 867 Quicksilver with a graphics card that has a DVI port and and ADC port. I think is is the GeForce2 MX w/32 mb SDRAMC. I have been using it with an old G3 17" Cinema display and connecting via the DVI port with an adapter.

I just bought a used Apple M7649 17" LCD Studio Display. It connected easily to the ADC side of the graphics card, but showed no picture when I booted. However the power button lit up and functioned on the front of the monitor. Thinking I had to "Detect Display" from System Preferences, I powered down, connected both monitors, and booted. Same result for the new LCD monitor, but the old monitor showed only my desktop background picture--no icons or Dock. During the boot process there was no spinning fan and no thermometer bar as in a normal boot. If I power down and remove the LCD monitor from the ADC port, the G4 boots normally with the old monitor.

Is it possible that I have a graphics card that is functioning on the DVI side but not on the ADC side? Is there anything else I can try other than finding another Mac to test the Display? All ideas will be appreciated.

MacBook Pro, Mac OS X (10.6.6), G4 Quicksilver

Posted on Feb 27, 2011 3:02 PM

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Answer 1

BDAqua

Level 10

250,259 points

Feb 27, 2011 3:46 PM in response to Werz

Hi P1@ff, and a warm welcome to the forums! 🙂

Power Mac G4: Display Compatibility...

http://support.apple.com/kb/HT1825

2. The Power Mac G4 (QuickSilver) computer has an optional video card that will drive both an ADC and VGA display simultaneously.

But hmmmm, it didn't work alone on the ADC connector?

Did you try Safe Boot from the HD, (holding Shift key down at bootup), which should use a safe resolution?

Or set the Rez to 1280*1024, power down, disconnect the DVI monitor, connect the ADC & try booting.

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Answer 2

Werz Author

Level 1

35 points

Feb 27, 2011 4:22 PM in response to BDAqua

BDAqua,

Thank you. I have tried the SHIFT-Boot and changing the Res as you suggested, but no luck.

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Answer 3

BDAqua

Level 10

250,259 points

Feb 27, 2011 4:28 PM in response to Werz

Did you try the Shift-Boot with just the ADC connected?

Also, perhaps the Backlight or inverter is bad on the ADC, next time it boots to that but nothing shows, use a flashlight to angle around & see if there's a dim desktop on it.

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Answer 4

Werz Author

Level 1

35 points

Feb 27, 2011 4:45 PM in response to BDAqua

Yes, I shift-booted with just the ADC connected. I'm not sure I understand the flashlight thing. I did shine around on the screen looking for a dim desktop, and I darkened the room looking for the same.

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Answer 5

Allan Jones

Level 9

78,386 points

Feb 27, 2011 5:05 PM in response to Werz

The ADC carried, video signal, power and USB. Try attaching your mouse and keyboard to the USB ports on the ADC monitor and see if that wakes things. Older Mac monitors that had an ADB pass-through would allow only one resolution if the pass-through was not used. A long shot, but worth trying.

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Answer 6

Feb 27, 2011 5:34 PM in response to Werz

the old monitor showed only my desktop background picture--no icons or Dock. During the boot process there was no spinning fan and no thermometer bar as in a normal boot.

That describes exactly hwat would happen if the displays were put into Extended Desktop mode, and that was the "extra" display that shows the additional desktop Real Estate. The menuBar and dock could have been on the "dark" display.

So continuing along this line, take a bright light and shine it at the display screen, to see if only the backlight is what is missing.

I don't think the card you mentioned supports two displays. If you have a chance with the "good" display working, try to find out exactly what card you have installed. It may make a difference.

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Answer 7

Werz Author

Level 1

35 points

Feb 27, 2011 6:07 PM in response to Allan Jones

I tried connecting the mouse and keyboard to the usb ports on the monitor, but there was no difference.

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Answer 8

Werz Author

Level 1

35 points

Feb 27, 2011 6:10 PM in response to Grant Bennet-Alder

I tried shining a lit on the screen, but I couldn't see anything.

I looked on the system profile with the "good" monitor hooked up and it showed that I have the following card: NVIDIA GeForce4 MX 32mb.

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Answer 9

Feb 27, 2011 8:53 PM in response to Werz

That card IS dual-display capable.

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Answer 10

Werz Author

Level 1

35 points

Mar 1, 2011 6:47 AM in response to Werz

I took the monitor to our local Macman dealer where we plugged it in to their G4. It worked perfectly. I bought a used GeForce4 MX video card from them and the monitor now works great on my G4. It turned out that the ADC port was bad on my card.

Thanks for all your help, everyone!

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