SV25 - Bad caps?

[sgtmuffles]

Hi, a couple years ago I got a barebones SV25 by shuttle that worked most of the time but would randomly freeze, restart, and wasn't able to install certain OS's without aborting and giving me a really vague error (something like "abnormal error, install failed" really short) and quitting.

Another weird thing: It can't complete a full run of memtest86 (the bootable disc, not the in-OS one). When I hard-restart and try to run it again, it hangs sooner and sooner. That to me would imply a heating issue, since the first time you run it, it's cool and takes a while to heat up to critical temps, but the 2nd, 3rd, etc. time you run it it's already pretty hot and doesn't take as long. Also, it's happened when I've had it test just the first half of the memory and the second half.

I'd just shrugged and given up, but now, a couple years later, I stumbled upon this site and there are a few different references to the SV25 as having bad caps. They're even selling a kit specifically for it to replace the caps. So I opened it up but all the caps looked healthy and happy, not even close to the ones that are shown in pictures on the site.

Could this still be the caps' fault? Any thoughts?

[willawake]

Re: SV25 - Bad caps?

what do the caps in the psu look like
check your ram in another pc
chances are the caps on the board are off spec but not visibly failing it can happen

[Topcat]

Re: SV25 - Bad caps?

If the caps are 'Gloria', 'Lelon', or 'OST' brands, replace them. Those are the commonly used ones by Shuttle. I've recapped hundreds of SV25/FV25's, and NEVER had one end up a dud. With good caps, those are bulletproof little boards.

[willawake]

Re: SV25 - Bad caps?

those are bulletproof little boards.

oh god dont tell mikey

[sgtmuffles]

Re: SV25 - Bad caps?

Hundreds? Wow. Have them in a cluster or something?

I checked the brand, and it looks like they're OST. Would you say it's probably the caps that are causing my problems then? I don't have another computer that uses PC100/133 memory lying around, unfortunately, so I can't test the memory.

[sgtmuffles]

Re: SV25 - Bad caps?

Also, did anyone else find that attaching the HS/Fan was an extreme pain with this board?

[Topcat]

Re: SV25 - Bad caps?

Hundreds? Wow. Have them in a cluster or something?

I checked the brand, and it looks like they're OST. Would you say it's probably the caps that are causing my problems then? I don't have another computer that uses PC100/133 memory lying around, unfortunately, so I can't test the memory.

I'd bet that the caps are the culprit. The HSF's are those little low-riders, be careful not to break the clasps off the CPU socket removing them. Also be careful not to stab the board if removing them with a screwdriver.

If you don't think you can recap it, shoot me a PM, I can do it for you.


Ohh and Will, I'll have to add that machinegunning smiley... I added the one yesturday, and everyone seems to like it... lol

[linuxguru]

Re: SV25 - Bad caps?

The caps also fail in the small Channel-Well PSUs that the SV-24/25s usually come with. Recap all the Fuhjyyus on the secondary and you should be OK for 5-10 years.

[sgtmuffles]

Re: SV25 - Bad caps?

I've never opened up a PSU before and I've been told by instructors in the past that it can be pretty dangerous. What should I know before opening it up to check its caps?

[willawake]

Re: SV25 - Bad caps?

just dont mess around in it when it is plugged in to the mains
there is danger also if a psu has had a bad failure (if a circuit is broken the big caps wont discharge) if its still operational then dont worry about that.

you only need to pop the lid and look at the caps.

[sgtmuffles]

Re: SV25 - Bad caps?

So I opened up the power supply and here's what I see. The manufacturer appears to be "Teabo" or something like that and while most of the caps look fine, one seems to have vomited. There's a whitish-yellow now-hardened material spread between two capacitors and it looks like the rim of covering on the top has melted off or something. There are two other spots that have yellow now-solid goo in the psu. Take a look in the really poor quality (sorry) pictures attached.

[Topcat]

Re: SV25 - Bad caps?

^
There you go. Time to recap the PSU, and might as well do the board while you're at it.

[Tom41]

Re: SV25 - Bad caps?

So I opened up the power supply and here's what I see. The manufacturer appears to be "Teabo" or something like that and while most of the caps look fine, one seems to have vomited. There's a whitish-yellow now-hardened material spread between two capacitors and it looks like the rim of covering on the top has melted off or something. There are two other spots that have yellow now-solid goo in the psu. Take a look in the really poor quality (sorry) pictures attached.

I don't see any pictures attached to your post, nor in links - did you forget them?

If the capacitors have domed up and there is brown-yellow stuff spilling out of the top, it may well have vented. However, don't be confused - a lot of PSU manufacturers put glue on the components to stop them vibrating during use. If you see white-yellow stuff between the capacitors, but not at the top or bottom, it's probably glue. Glue is often a uniform color and opaque throughout, while spilt electrolyte will be varying color and semi-transparent.

If you're really concerned about high voltages in the caps after you disconnect from mains, take the blade of a screwdriver (or similar metal object) and short the pins on the base of each capacitor. That should get rid of any charge remaining in the caps from when it was powered on - you may even see a little spark.

The only reason you might want to run a PSU with the cover off is for testing a fan repair/replacement... better to make sure the fan is running properly before you close it up, than to find out it's still dead afterwards!

https://www.badcaps.net/forum/attach...tid=3583&stc=1
(not my pic) the yellow stuff here is glue...

https://www.badcaps.net/forum/attach...achmentid=2346
The stuff coming out of the bottom of these caps is electrolyte, now dried on the board.