Need help identifying caps

[BigBadBiologist]

A motherboard of mine is acting like it has bad caps.
http://www.gigabyte.com.tw/Motherboa...I865GM-775.htm

I've replaced the normal caps and the problem persists. There are smaller unwrapped sold can caps (like on a lot of video cards these days) around the CPU socket that look a little odd so I want to try replacing them, but I can't figure out what they are. The markings are:
4y1
561
2.5V

There is a symbol (I assume manufacturer symbol) sort of like anf F or E with a line directly above or below it. All printing is red.
_
F
_

Any help in identifying the capacitance value would be greatly appreciated (I'm assuming the voltage rating is 2.5V).

[kc8adu]

Re: Need help identifying caps

fujitsu solid polymer .
are the tops domed?
common failure with these.

[BigBadBiologist]

Re: Need help identifying caps

Thanks! Hopefully that will narrow down where to look for the capacitance values.

They aren't domed, but several look corroded/cracked on the side.

I already RMAed the board to gigabyte and they sent it back (after a month and half) in the same exact condition (board randomly shuts down after posting).

[linuxguru]

Re: Need help identifying caps

SMT Fujitsu SPAs rated for 2.5v? That's probably going to be tricky, both to get a replacement and to actually unsolder and resolder the replacement - unless there's also an outline for a leaded through-hole alternative around it.

[willawake]

Re: Need help identifying caps

can we have a pic please?

i doubt if they are smt

[BigBadBiologist]

Re: Need help identifying caps

I'll try to get a pic. My digital camera isn't the best, though.

They are through hole, but they look like the SMT kind that are on video cards and such.

[BigBadBiologist]

Re: Need help identifying caps

OK, I managed to get a decent pic.

[linuxguru]

Re: Need help identifying caps

The caps look OK to me - but SPAs can fail silently without bulging or leaking.

[BigBadBiologist]

Re: Need help identifying caps

I'm not totally sure if they are bad or if they are just not strong enough. Like I said before, several of them look odd on the sides (camera couldn't pick that up), but they get really hot when the system is on and the mobo randomly powers off. It is the same thing that happened to me once when I put caps on an 8kha that weren't the proper ESR rating.

[willawake]

Re: Need help identifying caps

have you checked in the psu to see if you have badcaps there. I am not sure about the brand of those caps. They appear to be 561uf 2.5v polymer caps radial lead

They are not fujitsu as they only offer the yellow ones in radial or bare aluminium smt type only. neither are they oscons. assume the worst i guess.

you could recap them with 1000uf 6.3v. better to use the lowest esr caps you can find. are those caps 8mm. you will have to find same width replacements.

[BigBadBiologist]

Re: Need help identifying caps

I've tried 5 different PSUs, 3 different CPUs, and 3 different sets of RAM (all of which work fine in other systems) so I'm pretty sure its the mobo.

The main problem is HSF clearance. I was thinking of mounting the replacement caps on the back just to test the system out and confirm that's really the issue... once I figure out exactly what they are.

Thanks for all of the assistance!

[kc8adu]

Re: Need help identifying caps

have you checked in the psu to see if you have badcaps there. I am not sure about the brand of those caps. They appear to be 561uf 2.5v polymer caps radial lead

They are not fujitsu as they only offer the yellow ones in radial or bare aluminium smt type only. neither are they oscons. assume the worst i guess.

the f logo suggests they are fujitsu unless impostors are now counterfieting these too.
and the 561 is the value.
first 2 numbers are the value and the third is the number of zeroes that follow.
so 560 uf.

[BigBadBiologist]

Re: Need help identifying caps

Nice. Thanks for the info. Someone on harforums also referred me to this:


I think I'm there!

[BigBadBiologist]

Re: Need help identifying caps

Well, I replaced the caps with 1000uF 6.3V caps and the problem persists, so that is a bit of a disappointment. The caps are getting really hot though, so it makes me think that they just need to be a higher voltage rating or something.

[AK0R]

Re: Need help identifying caps

The caps can be expected to run warm, but not hot. If you think they are unreasonably hot, then something else is likely to be the problem. You don't say what abnormal symptoms the computer is displaying, or the condition of the power supply. A 6.3v rating is more than adequate, if the original caps were rated at 2.5v. A possible cause could be high ripple, resulting from a degraded on-board VRM or back at the PSU. Can you measure the voltage across the caps, and if possible, also measure the AC ripple voltage?

[linuxguru]

Re: Need help identifying caps

You need ultra-low ESR types like the Rubycon MCZ or Samxon GC/GD to replace SPAs.