View Full Version : MD Power Mac won't boot up, fans still blowing.

Oct 20, 2009, 01:09 PM
I have a Mirrored Door dual 1 ghz G4. When I went to wake it this morning, I usually only put it to sleep, I noticed it had powered down. I pressed the power button and it did nothing. I then changed the power cord and when I plugged it back in the fans started blowing but that's all that happened. I don't know if you've ever heard a MD with all the fans going (wind tunnel) but that's what happens if I plug in the power cord now. Could it be related to the power supply? Fans all seem to work fine.

Oct 20, 2009, 01:11 PM
wind tunnel also happens when you have CPU failure.

Oct 20, 2009, 06:56 PM
Sounds like you've heard the old 'wind tunnel' before. What I find strange is that now if I plug in the computer, without even touching the power button, all I hear are fans and then the wind tunnel. I had an old Quicksilver years ago stop booting up like this one and I just scrapped it for parts but I would like to figure this out if I can. I realize it could be a number of things, processor, power supply, motherboard, ect. I guess I'll try the battery, I just replaced it a couple weeks ago, and go from there. I did find a similar post about the MD but it wasn't doing the whole thing with the fans. Any other ideas would be appreciated. Thanks.

Oct 20, 2009, 09:19 PM
I changed the battery and reset the pram and it's up and running again. My crappy day just got a little less crappy but there's always tomorrow.

Feb 12, 2010, 01:21 PM
we own a similar Mac ( g4, 1.25 GHz). It used to boot up and work normally
for many years. Since last month shuts down while on job..
Firstly i noticed that time was not correct and i replaced the small 1/2 AA battery and reset as u do. The time now is ok but is still shuts down without any profound reason...
The tower power led goes first off and then the monitor one. Some times we hear a "wind tunel" better "blower" sound. Pressing power button again boots
and some times goes to OS prompt where we write " mac-boot" and sometimes boots normally.
My friend insisted that the machine boots up without pressing power switch...
I didnt believe him .. but is true. One day our Mac was switched off for sure and out of the blue boots... i dont believe in ghosts :)
I am planning to replace power supply and fan, is a good idea??

Thanks in Adnance