Depending on which Apple mini-VGA to VGA display adapter you have,
one of them may work while others may not. The model M8639G/A or
one like it (has different number on original packaging) should work in
applications with iBook G4, eMac G4, PowerBook (some), and iMac G4.
• *It should work*, if you follow these simple rules: {avoid static charges when handling connector)
1) shut down your computer completely
before connecting the adapter; sleep-mode won't do.
2) power up the external screen or video projector
after connecting the cable and
before booting the Mac.
3) shut everything down
before disconnecting the mini-vga adapter.
The part number (on my package) says 603-0607; these fit snug in the
video-out mirror port on an iMac G4. The external display, if supported,
should appear in the Displays system preference panel, where it may
be selected and accessed by the computer. There may be other similar
products that look a lot alike, and may not work in certain computers.
I have the same model as this, and it works with a mid-2005 iBook G4
as well as a last series model iMac G4 1.25GHz 17" USB2.0.
Examples:
http://store.apple.com/us/product/M8639G/A - or -
http://www.amazon.com/Apple-Mini-VGA-display-PowerBook-603-0607/dp/B002PXV0S6
The web page images are helpful to show enlarged view of mini-VGA adapter ends.
There are other similar adapters which may fit, but don't have correct connectors.
Not sure of technical differences in those very similar in appearance.
The adapters may be able to work on any older G4/G5 within standard mini-VGA limits;
and the old
http://store.apple.com/us/product/M9109G/A adapter should also work, too.
However, the audio portion of this adapter may not work with the iMac G4; so another
cable setup could be used to provide audio from the headphone jack & other connectors.
(The similar adapter for use with early Intel-based MacBook has different wiring.)
What computer model did the adapter(s) you have, come with? What external video
display unit are you trying to use the adapter and iMac G4 with? There is a possibility
the adapter and/or the display aren't compatible with the iMac G4; or the video-out
port is damaged. However, testing the mini-video out port would require known good
adapters of the correct type.
Does the System Profiler, and also the System Preferences> Displays show an
attached external display when the connections are firmly made? One or both
should give some clue if there is some kind of connection; unless the port is bad
or the adapter is incorrect.
Are you going to be using a display or a projector with this? Some products may
require a different input signal frequency than these older computers generate.
Not sure on how else to check or troubleshoot the situation if the peripherals
do match up correctly, and nothing happens. However if an external display
does work but won't appear correctly, there is a third party app freeware able
to help adjust resolution and other settings. At least in OS X: SwitchRes X:
http://www.madrau.com/SRXv3/html/SRX/About.html
Hopefully some of this helps; at least to confirm the adapter details, and the
basic attachment process usually involved. The System Profiler should have
an indication of a correct connection; if the port or adapter is wrong/broken,
then this would not be a pointer to gauge success. Except by its absence...
For other methods of troubleshooting video, should the machine have an
issue and you need to use an external mirror display to access it, see this:
http://discussions.apple.com/thread.jspa?threadID=914904
Good luck & happy computing! 🙂
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