Mac Pro 2010 / 2012 PSU

[bax2003]

I just found out something interesting. My Mac Pro from sig, has AcBel PSU (614-0455). Few days ago I disassembled Mac Pro mid 2012 which has Delta PSU (614-0454). Both PSUs have exactly the same specs.

And now why this topic...loudest fan in my Mac iz Power Supply fan. Fan in both machines are running at the same speed, but mine is definitely louder.

Is there a chance that fans are not the same for different PSUs combinations ?

One more thing, is there a quality or reliability difference between these PSUs, because internally they are not identical ?

 

[bokkow]

Interesting find! Can you check the RPM of the PSU-fan on both systems (iStat / Macs Fan Control)?

I am guessing that both PSU's are rated within the same range of specifications and quality which makes it ok for Apple to use both manufacturers. Even with the same product type, Apple applies this more often with sometimes big differences (Sandisk vs Samsung SSD's in MBA, LG vs Samsung displays MBPr, etc).

 

[bax2003]

599 / 600 rpm....identical speed

 

[bokkow]

Maybe your PSU-fan has had more hours of spinning, could be the bearing is worn. What might help is a bit of carefully applied silicone spray between the fan and its bearing. Or just replacing the fan of course, I do not think the quality of the power delivery can be that much different between the two brands that it would make you want to replace the whole PSU.

By the way, be very careful when opening a PSU or any type of power supply for that matter; the capacitors might hold charge for a while and can be very painful/dangerous.

 

[bax2003]

I think that hardest part to change in Mac Pro 2009/2010/2012 tower is PSU fan. You have to remove backplane board to change it because fan cable is someow hitched behind it....probably to inside chassis.

To apply silicone, and do good job, you sould at least unhook it from metal cage, and doing that you will damage rubber rivets.

I did not even cross my mind to change PSU, but if someone with PSU experience looked inside of both of these, it would be nice to share any useful info

There are AcBel PSUs in Mac since G4 towers, maybe even earlier. For example, it is prooven in many cases that AcBel 360W PSU in G4 MDD is louder than 360W Samsung PSU in the same G4 model. In G5s, I think, only AcBel made 1KW PSU for 2.5GHz Quad.