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MP 1,1-5,1 Mac Pro 2008 power on problem
- Thread starter gigid
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- mac pro 2008 power
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Likely the Power Supply. For a machine that is now 13 years old the Capacitors in the Power Supply are likely bulging (they were never much good, in line with a lot of "consumer" electronics at the time)..... My cMP had an intermittent issue. Was cheaper to buy a replacement machine at the time (used and low-spec, but swapped the PSU out). Never had a problem afterwards.....
A view questions you might want to ask yourself:
#1 When was the last time of an OSX new install or OSX upgrade or Firmware upgrade/Apple security upgrade?
#2 How full is your boot drive, how much capacity is left?
#3 How healthy is your boot record, start up drive?
There are some software solutions out there that might be able to help to identify that culprit.
The argument from dave is valid, however the era of weak capacitors has been a lot earlier during the PowerMac G5 days. The age still affects those components, but I think the probability for boot drive errors, filled up startup hdd or super hot running Ram Modules are slightly larger. Speaking of hot ram, - if you have the 800Mhz modules in your 3.1, chances are that you have a dying ram module that causes problems during boot up. This is what you can check right away without any cost. Run your MP with the minimum amount of ram, see if the problem persists. By changing ram modules around and experience with different numbers and slots you can detect a defect module or confirm its not the culprit. The hot ram module was a known problem back in the day, there have been some mods around where people put additional fans inside the ram fan cage to reduce heat on ram modules. If you can't identify the problem, please get back and post your config in terms of used pci card, memory config (677 vs 800mhz), ssd & gpu.
One other bit the check on is the dust build up inside your CPU bay. If you have a clogged up Nothbridge heat sink, chance are your system is going through a slow heat death. Check on eBay for some instructions to remove the CPU bay and give you system a proper clean up with compressed air or a good vacuum with some brushes. This often helps wonders if your system never ever was cleaned up.
#1 When was the last time of an OSX new install or OSX upgrade or Firmware upgrade/Apple security upgrade?
#2 How full is your boot drive, how much capacity is left?
#3 How healthy is your boot record, start up drive?
There are some software solutions out there that might be able to help to identify that culprit.
The argument from dave is valid, however the era of weak capacitors has been a lot earlier during the PowerMac G5 days. The age still affects those components, but I think the probability for boot drive errors, filled up startup hdd or super hot running Ram Modules are slightly larger. Speaking of hot ram, - if you have the 800Mhz modules in your 3.1, chances are that you have a dying ram module that causes problems during boot up. This is what you can check right away without any cost. Run your MP with the minimum amount of ram, see if the problem persists. By changing ram modules around and experience with different numbers and slots you can detect a defect module or confirm its not the culprit. The hot ram module was a known problem back in the day, there have been some mods around where people put additional fans inside the ram fan cage to reduce heat on ram modules. If you can't identify the problem, please get back and post your config in terms of used pci card, memory config (677 vs 800mhz), ssd & gpu.
One other bit the check on is the dust build up inside your CPU bay. If you have a clogged up Nothbridge heat sink, chance are your system is going through a slow heat death. Check on eBay for some instructions to remove the CPU bay and give you system a proper clean up with compressed air or a good vacuum with some brushes. This often helps wonders if your system never ever was cleaned up.
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Yep, all valid points..... but the Capacitor issue was definitely not just related to G5 related timeframes. Cheap capacitors in a REALLY expensive Arcam AVR amplifier caused PSU failure for me only last year, and that was newer than the cMP. At least the OP has a few different options to try....
thanks
it does it also without HD and without RAM
the capacitors of the power supply are good on mesuaring
the capacitors are good on metering
but it can be the power supply, wwhen I switch it on and after booting I switch it off then it doesn't start I have to wait minutes, but I guess it doesn't get hot enough in one minute running...
the mac was working and suddenly switched off and then the fan started very fast. (the mac was not used for some weeks )
now it starts but if I switch it off (even after one minute) to start again I have to wait
I made a test using cpu loading app I left the mac on various hours, and was ok.
now it starts but if I switch it off (even after one minute) to start again I have to wait
I made a test using cpu loading app I left the mac on various hours, and was ok.
The capacitors in a 4,1 /5,1 PSU are Nichicons.
Nichicon is like the Mercedes of the caps.
I seriously doubt that Apple would have used cheap caps for the 2008....
Nevertheless all capacitors have an expected lifetime which is significantly decreased by high Temps.
@gigid : as mentioned by @AlexMaximus , You could visually check the amount of dust and clean the whole MP inside.
If you install e.g. MacsFanControl you can monitor the Temps of all relevant parts , perhaps the issue is heat related .
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