Mac Pro PSU

[KeriJane]

Hello.

I've got this killer monster dual-Xeon Mac Pro which is the best computer that I've used so far and.....
I'd like it to last.
I was a little suspect of the PSU in particular because of my G5 iMac PSU with the bloated Ltecs in it.

So, while I had the system apart for dusting I thought that maybe taking a close look at the PSU might be a good idea.... so today I disassembled , cleaned and inspected the PSU and even took some pictures.

The PSU is made by Delta and is rated at 980w output. It appears to have six 12V outputs of 11-18A each and one 5v standby rated at 5A. There do not appear to be any 3.3V or 5V outputs. The PSU has a total of four similar output connectors with 8-12 wires in each (keyed to prevent mis-connects). There is no internal fan, but there is a 120mm dedicated PSU fan mounted in the case.

Here's the Capacitor list, with the exception of one tiny NCC that was under a heatsink and gobbed down with glue and of course the ceramic disc and "other" caps:

3x NCC 270uf/450v KMD series
16x ??? 330 /16v Polymer caps marked "PS665"
6x Nichicon 2200uf/16v PW series
1x NCC 2200uf/10v KZH series
1x Nichicon 100uf/25v BT(M) series
2x TAICON 2200uf/10v PW series
2x TAICON 220uf/25v PW series
1x TAICON 220uf/50v PW series
1x TAICON 100uf/50v PW series

All caps appear to be standard sizes and in good condition. The PSU seems well constructed and when running the system is a paragon of Stability. And Silence. Speed too.

I was thinking that maybe it might possibly be a good idea to replace all of those TAICON caps even though they look OK. Or maybe just get all of the caps under 450v just to have on hand.

Does anyone have any idea who made those polymer caps?

Anyways, I've noticed a lack of information available on Mac internals, especially the Mac Pro. So this thread is about what the PSU looks like and a little bit about it. By the way, the motherboard appears to be Foxconn made and has a whole bunch of NCC on it.

Have Fun,

Keri
and her NICE CLEAN Mac Pro

[Scenic]

Re: Mac Pro PSU

i'd replace those taicons. i've seen too many failed ones...
in fact, i replaced all taicons on an ASRock board preemptively...
they all looked fine, but the board was kinda flaky...
like.. a freeze per month or a "you need to reboot your mac" message (yeah... it's a hackintosh ).. but RAM and HDD were both OK.
never had problems since i replaced the taicons.. (with Sanyo WGs)

those blue polys are NCC BTW

[apiacere]

Re: Mac Pro PSU

I got a used (obviously) Mac Pro 2008. The computer boots but immediately shuts down and reboot when I open Safari (or Firefox). Basically, with any App that requires some power the computer shuts down and reboot. I used a Kill-A-Watt to see the instantaneous power. As soon as, 250 W is reached, the computer shuts down. After checking multiple possible causes, I came to the conclusion that the PSU is problematic. So, I tried to purchase used ones from E-bay. After three purchases, I gave up finding a used one. All sellers just turned on the computer to see if it boots and the dismantle to sell. I guess the failure rate of this power supply is so high that even if I'm lucky I wouldn't be able to find a PSU which will last next a few years. Meanwhile, I found this thread. I'm just wonder if any one had replaced TAICON caps and this replacement cured the problem. I ordered some replacement caps for these TAICON caps and am waiting for the parts to come. The caps are cheap so I would like to give a shot. If anyone has an experience in repairing this PSU and share, I will really appreciate that.

[startergo]

Re: Mac Pro PSU

I got a used (obviously) Mac Pro 2008. The computer boots but immediately shuts down and reboot when I open Safari (or Firefox). Basically, with any App that requires some power the computer shuts down and reboot. I used a Kill-A-Watt to see the instantaneous power. As soon as, 250 W is reached, the computer shuts down. After checking multiple possible causes, I came to the conclusion that the PSU is problematic. So, I tried to purchase used ones from E-bay. After three purchases, I gave up finding a used one. All sellers just turned on the computer to see if it boots and the dismantle to sell. I guess the failure rate of this power supply is so high that even if I'm lucky I wouldn't be able to find a PSU which will last next a few years. Meanwhile, I found this thread. I'm just wonder if any one had replaced TAICON caps and this replacement cured the problem. I ordered some replacement caps for these TAICON caps and am waiting for the parts to come. The caps are cheap so I would like to give a shot. If anyone has an experience in repairing this PSU and share, I will really appreciate that.

I replaced the second PSU on my cMP5.1. I always buy them with the squaretrade warranty from ebay. It would be nice though to find a way to repair them

[apiacere]

Re: Mac Pro PSU

I may be wrong, but MP 3.1 (2008) PSU is more problematic than MP5.1 PSU.
Square trade or not, I ended up buying three non-working PSU in a row.
Luckily all sellers refunded after my description.
But, I don't feel like to try another one.
I will try to replace some caps. If I succeed, I will post here. Fingers crossed.

[PeteS in CA]

Re: Mac Pro PSU

I got a used (obviously) Mac Pro 2008. The computer boots but immediately shuts down and reboot when I open Safari (or Firefox). Basically, with any App that requires some power the computer shuts down and reboot. I used a Kill-A-Watt to see the instantaneous power. As soon as, 250 W is reached, the computer shuts down. After checking multiple possible causes, I came to the conclusion that the PSU is problematic. So, I tried to purchase used ones from E-bay. After three purchases, I gave up finding a used one. All sellers just turned on the computer to see if it boots and the dismantle to sell. I guess the failure rate of this power supply is so high that even if I'm lucky I wouldn't be able to find a PSU which will last next a few years. Meanwhile, I found this thread. I'm just wonder if any one had replaced TAICON caps and this replacement cured the problem. I ordered some replacement caps for these TAICON caps and am waiting for the parts to come. The caps are cheap so I would like to give a shot. If anyone has an experience in repairing this PSU and share, I will really appreciate that.

Do you know that one of the 12V outputs is dropping out? With only 12V power going to the MB, that means the various logic voltages are generated by DC-DC converters on the MB. The MB is also likely to have a supervisor circuit that will shut down the power supply. I suggest, if you haven't already, testing to be sure that the problem is not with one of the MB DC-DC converters.

Delta seems to get good life out of second-tier suppliers like Taicon, so 10+ years is a decent life for those output caps. They may be bad as you suspect. IIRC, Taicon is license-producing Nichicon series, so their PW series probably clones Nichicon's PW series.

[bosscharles]

Re: Mac Pro PSU

Hi all, I've got my hands on one of these PSU's. Works fine but it has a chirping noise. It's not coil whine. It sounds like a cricket is inside the power supply and sometimes a bit clicky. The power supply works fine, but it's noisy. I'm guessing it's some of the capacitors which are causing the noise. Any idea which capacitors it would be sensible to replace? None of them look bloated.

Thanks!

[stj]

Re: Mac Pro PSU

macs often get run 24/7, if the psu is over 10years old i would replace all the electrolytics in one go.