Tip - Mac Pro fails to boot up, no chime.

Question

I have a Mac Pro (Intel, 2008). Within the last 6 months, a situation with the Mac Pro has occurred twice.
While asleep, or shut down, I press the Power button to start up the Mac Pro leading to the following events:
the graphics card fan runs at full speed.
the LED indicators on the RAM cards all light up red.
the HDD's begin to spin.
the startup chime does *not* sound.
the screen does *not* turn on.
the fan does *not* slow down.
several seconds after pressing the Power button to start up the Mac Pro, it shuts itself down.
it is not possible to reset the PRAM. (the startup sequence does not proceed far enough to allow this to happen.)
resetting the system via the reset button on the mother board does not affect the situation.
replacing the PRAM battery does not necessarily correct the situation.
removing every HDD, RAM card, PCI card and cable does not correct the situation.
this is what has worked for me.
assuming that the Mac Pro is not powered up:
unplug the power cable.
press the Power button for 5 seconds to drain any residual power from the system.
let the Mac Pro sit idle for 12 to 24 hours. (10 minutes simply doesn't do it!)
plug the power cable in.
press the Power button to boot up the Mac Pro.
removing the HDDs, RAM cards, PCI cards and cables may or may not affect your situation.
the first time my Mac Pro booted after this procedure, only 4GB of RAM was recognised by the system. I shut down the Mac, removed and re-inserted the RAM cards and booted the Mac up again. the Mac then recognised all of my RAM (20GB).
hopefully, we'll see a new generation of the Mac Pro this year with *both* firewire and thunderbolt.
cheers all.

Answer 1

Hi Greg! Yeah good tips. I'd like to add a few other tips that worked for a few of us. I have a 2009 nehalem MPro, 16 cores, 4 used internal bays, 5870 (added in 2011), replaced main boards, power supply, memory and CPU modules under extended warranty. Several ATTO pcie sas cards (r380,h380) bla blah.
History:
Ok, we we moved the whole suite to new premises some months back and the transportation was safe and well and due to premises issue, the setup above Nd the disk arrays etc sat I. The packing for two weeks...
Issue:
Mac Pro would not power on some times.. Else it would power on and then after or during startup would shutdown.
Cure:
Did most of the steps you described and
1) pulled all the disks from bays 1-4, pulled all the pci hba card  including the ati 5870, pulled the two DVD player units and lastly, the CPUs and memory module unit.
2) cleaned all contacts with cans of clean compressed air of all the above
3) then proceeded to replace each component then powering up the Mac Pro and make sure the startup chime occurrs, then power the Mac Pro off.
4) I started with the memory module with a single DIMM in the memory, finally replacing them finally with all of them repeating step 3. I did find a bnd memory dimm doing this. Don't worry if the Simms are not inthe most efficient slots.. Fix this later.
5) replace the GPU card (in my case ati 5870) strap Nd shutdown
6) this time hold the power button in for at least 20 seconds and reset the SMC.. Wait for the squeal!,
7) then do one of the disks or the disk set that you start from..
8) restart.  .. Wait for it to settle. Power off
9) plug in the mainscreen display and restart .. By now it all should be ok.
10) power off again. Power up again with key board and restart and then shutdown
11) add/insert  each pcie Hba power up and. Reset the SMC AS IN STEP 6 and shutdown. Repeat for any other MAKE SURE THAT THE SPEED OF THE PCIE card matches the rating of the slot.   so remaining hbas.
12)  should be looking good by now.... So login and then shutdown
13) and remainder of the internal disks , power up and access file systems.
14) should u get the memory manager appear at startup and recommend to re-organise the memory Simms, then print the report or use your iPhone to record the display, shutdown and move the dimms s it requests.
15) lastly serially plug in other peripherals and see hat they can be accesses.
Summary: worth the effort NDS time. Macpro has been solid ever since.
Hth
Warwick