Hangs indefinately at boot screen (Mac Quad 2.66 Xeon running Snow Leopard)
Tragedy strikes! So Yesterday I turn the beast on, and the Apple logo boot screen hangs indefinately while the loading circle spins, won't boot up.
Tried booting to the install DVD, does not see the disc when holding 'C' at boot up.
Strangely it sees the install disk when holding option, showing system drive and install dvd. However when DVD selected, spins up, hangs a bit, and then displays the grey, multi-language restart error "You need to restart your computer. Press the restart button or hold power button for several seconds to power down" (paraphrasing of course).
Attempted to flash the PRAM, didnt take the key commands or double chime, unable to flash the pram for some reason...
Some details and questions that may be relevant:
-System drive nearly full. Backed it up to the separate internal Time Machine drive i have in the tower, the night before this occurred..
System drive still has 4 or 5 gigs left though....
so thought it could be system drive not mounting, easily remedied. However the fact that the cpu wont boot from the Install DVD has made me question whether this has anything to do with the system drive at all.
-Later, right before I gave up and simply shut the system down, i suddenly heard a grinding sound. Looked inside the chassis, found one of the two small fans that sit atop the Accellero heat sinks was dislodged and sputtering about. Shut down, popped the fan back into place (these simply clip onto the heat sink via plastic clips that go between the fins). Turned on, spins as normal, no noise. Wasnt hot inside the machine and fans were spinning normally before that incident as well...
Not sure if related. If someone has had problems with the Accellero heat sink unit or its related fans and wiring, let me know what to look for and I'll take a more detailed look inside the chassis...
-Not sure if heat or power related, but place is cool in here, have multiple air conditioners. Could it be a bad switching unit in power supply? Machine turns on, stays on, but refuses to boot, maybe a single component not recieving enough juice via a minor power problem?
-thought it might be the well documented PRAM battery issue, but that usually renders blue screens at boot up. Possible?
-DID attempt to flash the PRAM at boot up, did not accept the key commands, did not doublechime, cant seem to flash PRAM
your insights are very appreciated! My music making rig is now down and im heartbroken...
Mac Pro, Mac OS X (10.6.7), Xeon quad core 2.66, 6gRAM