Fixed: Shuttle XPC Power Supply by ACHME

[TahoeEd]

A family member was having problems with a Shuttle SK43G computer that I built for them a few years ago. They were experiencing occasional instabilities, as well as an intermittent delay or pause between pressing the power button and having the computer turn on. It was kinda freaky pressing the power button and having it turn on 5 minutes later!

Anyways, all the caps on the motherboard looked fine, even though not being the best of brands. I remember some OSTs on the mobo. The problem turned out to be in the power supply. Most of the caps in there were bulging and leaking. Unfortunately, this is a small & proprietary power supply and replacements are hard to find, and not cheap when you do. It is an ACHME AM630BS20S.

I replaced all 10 caps with Nichocon HZ and HM from Mouser. There was one 220/25/6x12, and I had to squeeze an 8mm PW in there. I only made one mistake and didn't order a 470/16, so I used a 680/16 in its place. oops. The machine has been stable and turns on correctly. I'm a little disappointed that the +12V rail is showing 11.39V, that seems a little low.

I really like these little Shuttle XPC boxes, and I hope this post helps someone else rescue one of them.

[Per Hansson]

Re: Fixed: Shuttle XPC Power Supply by ACHME

Welcome to Badcaps and congrats on the success

Just a FYI; many mobos are very inaccurate with their voltage readings, use a DMM to see what 12v really is if you really want to know

[lat]

Re: Fixed: Shuttle XPC Power Supply by ACHME

Thanks so much coz this power supply difficult to find document.

Lat

[gustie]

Re: Fixed: Shuttle XPC Power Supply by ACHME

heh nice job

thats some tight area to work in!!

[pentium]

Re: Fixed: Shuttle XPC Power Supply by ACHME

I have to recap one of those soon as well. God they are so cramped.

[Rob]

Re: Fixed: Shuttle XPC Power Supply by ACHME

The +12v rail on my shuttle PC is 11.24V and that is how it was when I bought it. Somehow I think it conserves power since it is an Active PFC power supply.

[Per Hansson]

Re: Fixed: Shuttle XPC Power Supply by ACHME

Rob; lowering voltage does not conserve power
Quite the opposite actually

Google for Electric Current

[tazwegion]

Re: Fixed: Shuttle XPC Power Supply by ACHME

The +12v rail on my shuttle PC is 11.24V and that is how it was when I bought it. Somehow I think it conserves power since it is an Active PFC power supply.

Did you measure that at the CMOS, within the OS, loaded OR freestanding? I ask because the Asus supplied PSU I repaired recently also had PFC and I noted readings varied based on system loading (even lower when standalone)

[Joseph67]

Re: Fixed: Shuttle XPC Power Supply by ACHME

Thanks TahoeEd,
My shuttle started yesterday to switch off and my first thought was...PSU!
In order to be able to access the www, I connected a standard size PSU externally so I'm not without PC.
I also checked for "pregnant" looking caps, but as you say, they all look fine.
From earlier repairs on PSU's I found that often the 5V standby (pin9-Purple wire) is either gone or very low and I will start looking into that direction (the Cap. at the wire connection on the PCB). if that will not solve it I'll do the same as you did, replace all the cap's.
My added difficulty here (Madrid/Spain) is that decent brand cap's are hard to find.
Best place worldwide is in Tokyo/ Akihabara area.
There are like market stalls and each of them specialize in a sort of components like, capacitors ,resistors, Potentiometers etc,...
Thanks for the pic's, it save me time to make the drawings myself.
Cheers, Joseph.

[seanc]

Re: Fixed: Shuttle XPC Power Supply by ACHME

I've fixed quite a few PSUs like this now, usually Shuttle branded - they're all working nicely.

[Joseph67]

Re: Fixed: Shuttle XPC Power Supply by ACHME

Thanks TahoeEd,
My shuttle started yesterday to switch off and my first thought was...PSU!
In order to be able to access the www, I connected a standard size PSU externally so I'm not without PC.
I also checked for "pregnant" looking caps, but as you say, they all look fine.
From earlier repairs on PSU's I found that often the 5V standby (pin9-Purple wire) is either gone or very low and I will start looking into that direction (the Cap. at the wire connection on the PCB). if that will not solve it I'll do the same as you did, replace all the cap's.
My added difficulty here (Madrid/Spain) is that decent brand cap's are hard to find.
Best place worldwide is in Tokyo/ Akihabara area.
There are like market stalls and each of them specialize in a sort of components like, capacitors ,resistors, Potentiometers etc,...
Thanks for the pic's, it save me time to make the drawings myself.
Cheers, Joseph.

Not much luck with my PSU.
After replacing the caps, it is still not working.
Checking a bit further I found 2 faulty transistors and have localized one- the 20N60c3.
The other one has only -L99321- on it and it is not even known here.
Anybody knows about a replacement for this?
Thanks,
Joseph-

[nealc]

Re: Fixed: Shuttle XPC Power Supply by ACHME

Another vote of thanks for TahoeEd from me, as I have just brought my Shuttle back from an early grave by re-capping the PSU.

The failure mode on my system was slightly different from others described here. Usually, my shuttle powers up with the fan going full-speed, then the speed (and noise) throttles back after about 0.5s as the system starts to boot.

When my system started to fail, the fan would come on full-speed and never throttle back. I'd power-cycle it or leave it turned off for a few minutes then restart it and it would be fine. It took a couple of months to go from this state to a permanent will-never-start -- and the couple of days before it died, it locked up (almost unheard of).

£5.00 worth of caps (plus £5.00 worth of postage-and-packing) and two hours soldering later, it all seems to be fine again.

Ironically, I borrowed an old but unused PSU from a friend's spares box, to verify that the motherboard was OK. It powered up fine, but about 5s later the borrowed PSU started belching brown smoke (whilst still operating). Later investigation showed bulging and ruptured caps.. the same Fuhjyyu brand as my Shuttle's ACHME PSU.

Thanks also to all of the posters here, for making me not feel wierd about getting something working again rather than tossing it in the trash.

Neal.

[Altairat8te38]

Re: Fixed: Shuttle XPC Power Supply by ACHME



Can you tell me what psu you had on that shuttle? I would like to know where you got the caps as im in the uk.

Thanx.

[Scenic]

Re: Fixed: Shuttle XPC Power Supply by ACHME

check this thread for web stores selling caps.
Topcat (site & forum owner) also sells worldwide. Badcaps Store
If it has to be ebay for some reason, there's the PC Motherboard Capacitor Store (PCMCS) located in Hong Kong. That guy and audjade_chn are the only ebay sellers I'd trust for getting orignal (ie non-fake) caps. The PCMCS guy is aware of the fake cap crap.
Then there's Big Pope (forum member here, allthough I haven't seen him for quite a while) selling Samxon caps. http://capsmod.net/caps/

[malman]

Re: Fixed: Shuttle XPC Power Supply by ACHME

I have gathered capacitors and was about to start replace them but found the PWM controller ic blown, missing its cap. New KA3842AN can be found, but on the backside of the PWM controller board there is a small SMD resistor witch has gone up into smoke, burning the markings so i don't know what resistance to replace it with.
Has anybody got a clue what value resistor ASR2 shall be? (It's placed on the back side of the small sub-board witch is close to the DC output wires. The resistor is close to the edge nearest the big input capacitor 82u/450v.)

Help much appreciated.

/Klas

[selldoor]

Re: Fixed: Shuttle XPC Power Supply by ACHME

A good clear picture of the area might help, also smoke mark/burn might rub off with
some isopropyl alcohol. Have you got it off the board - may have markings underneath.

[malman]

Re: Fixed: Shuttle XPC Power Supply by ACHME

Okay, fixed some acceptable picures:


No big hope of finding any remaining markings on this one.

/Klas

[CdTe]

Re: Fixed: Shuttle XPC Power Supply by ACHME

I just fixed PSU replacing two Caps, C14 & C15 (1000uF/10V). Caps are located on both side of the purple wire in PSU (standby voltage, 5V).

Before fix I measured voltage being 3,2V in purple wire. After pressing power button Shuttle took 30s to switch on and the voltage reached 3,35V.

After replacing Caps the voltage is back to 5V.

Using external power switch you'll save the PSU lasting longer. Standby voltage is on all the time when the 230/120V cable is connected.

P.S. -> malman

I checked the Resistor ASR2 value. It's 512, 5.1kohm

[Joseph67]

Re: Fixed: Shuttle XPC Power Supply by ACHME

Hi CdTe,
Good job and indeed, most of the times it is just some of the cap's going bad and showing it off by their pointed hat!
Also, by powering off completely you also save several ten's of dollars a year on waisted electricity!!
Cheers, Josep.

[TomFortune]

Re: Fixed: Shuttle XPC Power Supply by ACHME

Hi guys
I have the same Achme powersupply also found in a shuttle pc. i am having a problem whereby ive changed three blown 1000uf 10v, TOP222y transistor and the built in fuse on the board. I was hoping for the powersupply after changing theses components to fire up but all i seem to get is a faint buzzing/humming noise from the output side of the board. I replaced the transistor as the whole unit had blown each leg away from the body of the transistor. Any help would be much appreciated.
Many Thanks
Tom