Mac Pro 3.1 problems

[joe10190]

Hi i am having a major issue with an old mac pro 3.1. It was working fine for general light use for a couple of months. I moved the parts from a battered old case to a better case. I also tried to upgrade the cpu to 2 x x5472 that i had lying around from a dead pro 3.1. 2 birds with 1 stone and all that. I have replaced 40/50 windows motherboards so was reasonably confident of moving it ok. I now cannot get the machine to work properly.I went back to the tried and tested x5462 for now.
the machine is completely dead with the cmos battery in, though the front power light is on when power cable is connected. the led light only shows a green light on the power trickle led when pressed. If i take out the cmos battery the machine powers on when the cord is connectted , the fans turn on and the chime is heard, and the os loads. The front power light is always on and does not respond when pressed
i have tried both 2 psu and 2 harnesses
what i have i done wrong??????
help!!!!!!!!!!

thanks
darrell

 

[Roman78]

The new case is also from a 3.1? Try the frontpannel from your working one, maybe there is some failure.

 

[joe10190]

thanks for the reply. frontpanel also from another 3.1, will swop front panel over later.
darrell

 

[parisinvest]

thanks for the reply. frontpanel also from another 3.1, will swop front panel over later.
darrell

in my experience of reparation Macs, you may want to check your psu or your cpu, try to put back the ancien cpus with lowers frequency, to see if it starts, and if not move the psu out and try to power another Mac Pro, if not your logic board may have a problem, it's not you did a right way to replace or not, it's just its' time is up sometimes, bon courage !
btw I'm not sure x5472 will work on mp 3,1, mine solution is always x5365 for 3,0ghz

 

[Roman78]

X5472 works on MP 3.1. They were one of the default CPU's. I would say the x53** won't work.

 

[parisinvest]

X5472 works on MP 3.1. They were one of the default CPU's. I would say the x53** won't work.

I've just checked apple forum for these cups, you are right about x5472 or x5482, they supported mp3,1 but with two different series, one work, another one doesn't, but all series x5355 x5365 works with mp3,1

 

[joe10190]

thanks for the replies. i have gone back to the x5462 cpu that were working fine and back to the psu that i have been using for the past 2 months. the plan was to test the x5472 cpu and then sell them if they are ok.
i still need to sort out the powering up issue.
thanks
darrell

 

[tsialex]

Only SSpec SLAxx Xeons work with MP3,1, SLBxx don't work.

Always check the Mac Pro CPU Compatibility List before trying a Xeon into a Mac Pro.

 

[joe10190]

x5472 pulled from a dodgy mac pro 3.1 so i am sure they are compatible.
thanks for the reply
darrell