Blew my power supply

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Colt45ws

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Not a week after I made this post talking about my old system with 50,000 hours in Nick's thread that I shut my system down to do a hardware change and the power supply drops dead as soon as the computer shuts off.
No 5VSB output. I couldn't figure out why it died literally the moment it shut off. My motherboard has a blue lit switch built on that is always on if it has power and it went out as soon as it shut down.
So, I had to think for a bit, then I remembered I read a review of my power supply, a Cooler Master UCP 900, that it has a mini power supply on a separate board that provides 5VSB.
When the computer is running, the main supply shuts off the mini-5VSB board and supplies 5VSB off of the 5V rail. So something had gone wrong with the miniboard while it was running and when the supply shut off, it turned it on and...poof!
It even blew the fuse on the main board, which is bizarre because I cant see any exploded parts. Its a 15A fuse so one would think something would've gone ka-boom!
But I managed to get it running again with two power supplies to feed it. A Seasonic 520W and a Zalman 600W.
Now I need to look for a good supply about 1000W.
 
The capacitor and/or resistor may be burnt.

You can open it up and see if any of the capacitor is bulging.
A lot of these gadget uses cheap capacitor from China that is not so long lasting compare to the old tube TV.

Unfortunately, it is probably cheaper to buy a new PS.
 
Yeah, I did open it up. There is one cap on the main board that has spilt its guts, but, Im not too keen on replacing caps as I don't see a couple of bad caps blowing a 15A fuse. Something else died in there and I don't know what.
 
Pretty sure.
I have an overclocked i7 980x and two 6970ish cards (they are 6950s running 6970 shader count but not 6970 speed...basically I have the same thing as a single 6990) and 8 hard drives
1000 is an over-safe number. If it was 850-900 I would probably be okay with that too. I did say about 1000w.
 
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Originally Posted By: Colt45ws
Yeah, I did open it up. There is one cap on the main board that has spilt its guts, but, Im not too keen on replacing caps as I don't see a couple of bad caps blowing a 15A fuse. Something else died in there and I don't know what.


Oh, caps certainly do have the ability (almost wrote capacity, har har) to create a short. If this cap is on the input rectification side just check the diodes and make sure they aren't open or shorted. If they appear okay I would replace all the electrolytic caps. Also check for a transient voltage suppression device (looks like a diode) on the input side. Those seem to age poorly once in a while and they absolutely will blow the input fuse.
 
Yeah, Im going to give it a through go-over probably later tonight. I just put it to the side until I got it back up and running again with the dual-supplies.
It also kinda aggravated me they didnt put the AC input leads on a connector, just soldered straight to the board.So I have to desolder them and I just put it to the side for a bit.
 
Yup! I consult that site all the time. Unfortunately I found it right after I bought this Cooler Master supply so I only found out it had Ltec caps in it then. And I found the limit of them is about 5 years of continuous use. Ie. I should've recapped it as soon as warranty was out.
Aw, well.
Yeah, Im actually looking at the 850 RMx and the EVGA 850 P2 right now. If I can't figure out what broke on my UCP then one of those two (whichever is cheapest)
 
Originally Posted By: Colt45ws
Yeah, I did open it up. There is one cap on the main board that has spilt its guts, but, Im not too keen on replacing caps as I don't see a couple of bad caps blowing a 15A fuse. Something else died in there and I don't know what.


Your right. The swollen caps usually open which will shut down the supply and not blow fuses. Shorted electrolytics is far more rare than open ones. I have found in so many situations that if a device has been running long hours non stop, the power supplies will not come back to life if they are shut down. It was on its last legs to begin with, toss it, not worth messing with.
 
The bad cap probably caused one of the actual mosfets to fail shorted, which blew the fuse. Not worth fixing.


Anyway, of the RM and the G2, I'd go for the G2. I like Superflower's leadex platform a bit better than the CWT design used in the RM. Plus, superflower tends toward better build quality and soldering over CWT.

EDIT: Oh I see you got the Corsair after all. Not a bad pick at all.
 
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Just replace with something better.. take the time to upgrade to a 80+ gold or platinum.

Good idea.
 
Originally Posted By: kc8adu
post on badcaps forums with good pics.
its likely worth fixing.

I did. I haven't worked on it yet (so far the only suggestion has been to do a bunch of resoldering on some dry joints)
I will probably later this week.
Even though I have a new one, it would be nice to have a large backup supply since my largest is only 600w atm.
 
Don't waste your time. Only way to test that switching P.S.after recapping is to put a load on it by connecting it back up.To blow that fuse, you got a dead short somewhere not a cold solder joint or an open, buldging capacitor. To me, I got better things to do than to resurrect an inexpensive, high mileage power supply.
 
Originally Posted By: Lubener
Don't waste your time. Only way to test that switching P.S.after recapping is to put a load on it by connecting it back up.To blow that fuse, you got a dead short somewhere not a cold solder joint or an open, buldging capacitor. To me, I got better things to do than to resurrect an inexpensive, high mileage power supply.

Guy can't have a hobby?
Besides, I aint doing much since I got laid off in Sept.
 
Its in and its running!
rm850_1.jpg

I had opted to install it upside down, thinking, since its semi-fanless, when the fan shuts off, the heat can still rise out through the fan opening.
But watching it, turns out that even idling on the desktop, its not shutting off.
Sooo, I may flip it later.
I have a new top I/O panel coming from Cooler Master for my case. I stepped on a cord and totally destroyed a USB socket quite awhile ago and the part finally came in stock. So I should have it next week or so, but Im going to do a modification to it before I install it.
When I bring it down to run all the I/O cables down to the board Ill revisit flipping it.
rm850_2.jpg

Yeah, its a mess, always has been. My USB 3 card has to have aux power via a molex. Right after this was taken, I flipped the routing so the last molex on the chain is powering it, rather than the first. Boy, its pain to get it out of that card, I wished they'd used the floppy mini connector, but as it was, I had little selection for cards. There is a heatsink directly behind the top PCIe x1 slot its in, so that was my only requirement when I bought it was that it fit where I wanted it to.
Oh yeah, I dropped my Sound Blaster card and moved my RAID card to the PCIe x4 slot above the first graphics card that it was in.
This was what I did when the UCP died.
I did this so the bottom graphics card would have the full x16 link, as my previous placement had the RAID card in the very bottom slot and this causes the slot that the card is in to go to a x8 link.
I have to find a good, repeatable test to tell if it did anything, though.
rm850_3.jpg

I Liked the flat ribbon cables for about 10 seconds, then I realized it was more of a pain to do this than with the conventional sleeved cables.
rm850_4.jpg

I mean, really?
I looked around on Corsairs site, and it doesn't look like they sell regular sleeved SATA cables for this. Too bad.
 
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