29 Jun
2012
29 Jun
'12
8:36 a.m.
On 6/29/12 1:24 AM, George Rachor wrote:
The power indication goes out immediately when
letting go of the button.
I hear the disk drive start.
I can hear the fans start as well. After about 5 minutes the fans start speeding
up faster and faster.
(I pulled the plug at that point)
The fans speed up because the system didn't boot, so the power management
microcontroller goes into
failsafe mode (fans full on).
You should see the caps lock key flash once as Open Firmware starts up. If OF doesn't
come up, try reseating
the DIMMs. The light flash will let you know if USB is working.
<cmd><opt>RP resets the parameter ram, and it should loop through the OF light
flash sequence if you hold
the keys down. That may be enough to get video going.
<cmd><opt>OF breaks into the Open Firmware command loop. You should at least
be able to tell if the video
is working by doing that.
Holding the mouse key down will open the CD tray. That is another clue as to how much of
the system is
working.
If the machine was in an unknown environment, you should try to blow the dust out of the
power supply in
the bottom (which isn't an easy thing to do). Many supply failures occur because of
bad air circulation.
The problem with batteries occurred mostly on the Q605 systems, because the ADB
microcontroller drew too
much power. Battery issues got worked out over time as the microcontroller folks got more
experience with
power management on desktops.