Trickle power

StuartJ1210

macrumors newbie
Feb 13, 2019
5
2
0
UK
Hey could someone please help diagnose the problem i am having with my 2008 mac pro.

The Mac show's the 2nd yellow light when I press the diagnosis button on the logic board, after searching online this leads me to the answer of trickle power?

Now this seems to be an un answered question online and after speaking with apple on chat,they could not tell me the root cause of said trickle power, if its the power supply or something else not allowing my Mac pro to boot, apple suggested i take my mac to kent and pay for someone to tell me the answer as they do not support the 2008 mac pro anymore,this is also known as standby mode, so I'm at a loss
 

StuartJ1210

macrumors newbie
Feb 13, 2019
5
2
0
UK
Curious about whether the fans run for 5 seconds and then it powers off.. Had a 3.1 (2008) Pro that did that and it was the power supply that was blown.
Hi I've tried the mac again and it boots for 11 seconds I can hear the disc spin up
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During initial power on only? If so, it could be a blown PSU. Check the procedure in the service manual. I’m going to think optimistically here.
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Hi I've tried the mac again and it boots for 11 seconds I can hear the disc spin up
[doublepost=1550251503][/doublepost]
20190215_171954.jpg
I have managed to get a bong white screen an apple logo and the bar starts to load the off
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[doublepost=1550252491][/doublepost]I'm up to this screen should I go recovery or normal boot HD
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During initial power on only? If so, it could be a blown PSU. Check the procedure in the service manual. I’m going to think optimistically here.
****ing yessssssssssss took 32 gigs of ram out put in the original 4gb and pow its alive
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During initial power on only? If so, it could be a blown PSU. Check the procedure in the service manual. I’m going to think optimistically here.
Thank you Alex for attempting to help me out cheers have a good weekend peace
 
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Alex Sanders74

macrumors 6502
Nov 26, 2013
272
59
0
Toronto, Canada
Bum stick of ram. Lovely. At least that’s better than a PSU. Glad you got it resolved. Try each one to find out the culprit and bid it a fond adieu.
 
Last edited:

StuartJ1210

macrumors newbie
Feb 13, 2019
5
2
0
UK
Bum stick of ram. Lovely. At least that’s better than a PSU. Glad you got it resolved. Try each one to find out the culprit and bid it a find adieu.
Indeed, funny things happening now if I open safari and type Google the mac shuts off been using logic fine I have Yosemite any idea's???
 

Alex Sanders74

macrumors 6502
Nov 26, 2013
272
59
0
Toronto, Canada
Intermittent shutdowns are not fun. This seems like a power issue. What PCIe cards do you have installed? Also what drives?

Try downloading MacsFanControl and see if any of the sensors are showing high temps. I’m thinking your northbridge chip might be contributing but I think on these towers, the heat sinks are totally different to the 4.1 and 5.1 towers.

Any ideas other genius’? Tsialex?
 
Last edited:

Alex Sanders74

macrumors 6502
Nov 26, 2013
272
59
0
Toronto, Canada
Just was reviewing some posts and not sure if you ever got this solved. One of your screenshots is showing a system clock error which I didn't notice before. This is usually the battery on the logic board being dead and a replacement can fix erratic behaviour like you're having.