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Mustang Sally · Oct 18, 2006, 02:00 PM

G5 1,8 dual processor, early 2006:

Has problems turning on, not allways though, to keep me searching for the malfunction..

I press the button, the engine starts running, the first screen opens with the mac logo and than I eather do or don't seen the litlle smart ass clock start spinning. No idea why it does this. I have to turn of the power externaly and try again when it wont start up.. I had it checked for hardware problems, nothing wrong. Clueless once more.. Thanx for helping out!

More Mustang than Sally, Amsterdam

houltmac · Oct 18, 2006, 02:41 PM

I'd reset the PRAM, boot to the install disk and repair permissions as well as the disk, then try an Archive and Install.

If all else fails try loosening the heatsinks and then tightening them back up again; this seems to solve a multitude of problems.

reader50 · Oct 18, 2006, 04:39 PM

Stay away from hardware mods like the heatsinks until last. Those are the ones that can void the warranty or break expensive things.

Start up in Verbose mode, by holding down command-v during startup until text appears. If the startup goes normally, the text will presently vanish and show you the usual login process.

If the startup hangs, the last dozen lines of text will usually give us a clue as to where the problem is.

Mustang Sally · Oct 19, 2006, 05:47 AM

Okay, thanx a lot, will do that right now! If the following information is a usefull clue, the little white led above the starting button sometimes starts burning slowly and sometimes flashes when I turn the computer on, thats when it wont turn on. Allthough not allways..

Groetjes uit Amsterdam!

Mustang Sally · Oct 19, 2006, 07:51 AM

Okay, did the startup, went normally, so no extra information yet. I will keep doing this whenever I start up. About resetting the PRAM, could you be a little more precise? Needless to say, I'm no expert with mac's.. sorry..
Thanx so far!

Mustang Sally · Oct 19, 2006, 08:29 AM

command, option, P&R, found it!

Mustang Sally · Nov 15, 2006, 03:27 AM

by the way, when the startup 'hangs', it does not respond to command V, it keeps spinning faster and faster and starts to sound like a jetengine. I think it wants to fly away!

reader50 · Nov 17, 2006, 01:18 AM

That is an extremely early hang. The startup sequence goes something like this.

Press Power Button
Firmware tests run, looking for hardware changes and doing some very basic diagnostics.
Firmware code locates the boot drive, or if a few other startup keys are pressed, goes into specialized modes.
Hangs here are almost always hardware-related.

Apple Logo Appears
A stripped-down version of the OS has begun to load from a hard drive. The logo is supplied from software, not the firmware, so files have definitely loaded from the HD at this point.
Hangs here could be caused by HD problems, or hardware issues. Problems with peripherals are less likely because the system isn't looking at too many of them yet. The main video card is an exception, since the system has to minimally use it to display the logo, etc.

The activity wheel begins to spin
A stripped-down OS version has loaded and is doing some extra tests to make sure the hardware is compatible with this OS version. Probably does a very basic RAM test also.
Hangs here may indicate your OS version was intended for a different Mac model. Could be an OS problem, could be peripheral problems. An incompatible USB device perhaps.

OSX Welcome screen replaces activity wheel
Main OS is booting up.
Hangs here are almost always caused by software problems.