Need help identifying these caps!

[theOracle]

what amount of capacitance are these and what brand and what type?
and are they a type that has been known to fail?

they are about ~12 years old.

I am assuming the 4 in the top pic are 100 uF and 35V
and the one on bottom appears to be 47 uF and 50V

so I guess my main question is what brand and type are these and are they low ESR and especially, are they known to fail much? - I do not see any visual signs of failure, but I am suspecting them.

[Wester547]

Re: Need help identifying these caps!

Those are most likely Nichicon UX.

Datasheet.

They are general purpose SMD electrolytic capacitors from Nichicon rated for 2,000 hours at 105*C (excepting the 160V ones and higher which are rated for 3,000 hours) in terms of load life and 1,000 hours at 105*C on the shelf. The datasheet seems to specify the same "2P" markings present on those capacitors in the image. Couldn't know if they are the issue without measuring them. However, I believe Nichicon WX (2,000 hours @ 85*C 5.5mm tall GP SMD lytics from Nichicon) have been known to leak from the bottom with old age, but I haven't seen any leak on Intel motherboards within the last 10-13 years, probably because they're not in stressful locations. The "A3" and "B4" markings on the SMD capacitors in your images likely mean that they were produced during the 3rd week of January, 2003 and the 4th week of February, 2003, in accordance to Table 12 of JIS C 5101.

[theOracle]

Re: Need help identifying these caps!

I have a stock of very high quality low-ESR, 105C, through-hole caps from the manufacturers at the bottom of my signature and considering replacing these with them!

by the way, your date decoding jives!

everything else on this board is super high reliability, that is why I suspect the caps
"it's always the caps" as the saying goes (lot of truth in that saying)

[theOracle]

Re: Need help identifying these caps!

Here is what I am unclear on, I can see now that these are definitely Nichicon, and I see the high temperature marking, but how do you know they are the UX series, it seems like there are about 20 different Nichicon chip-type SMD electrolytic series - how do you identify the series? - like why couldn't these be UD series, for example?

[stj]

Re: Need help identifying these caps!

i dont tink it's Nichicon, that leaning over "o" symbol looks familiar.
it may be korean - pos samsung.

[Wester547]

Re: Need help identifying these caps!

That "O" symbol is on Nichicon SMD lytics, affirmed in the datasheet.

Here is what I am unclear on, I can see now that these are definitely Nichicon, and I see the high temperature marking, but how do you know they are the UX series, it seems like there are about 20 different Nichicon chip-type SMD electrolytic series - how do you identify the series? - like why couldn't these be UD series, for example?

Because Nichicon UD capacitors have "UD" marked on them.

UD datasheet. Those are most likely UX judging by the voltage ratings on those capacitors. They could be WF but WF doesn't go up to 50V.

[theOracle]

Re: Need help identifying these caps!

i dont tink it's Nichicon, that leaning over "o" symbol looks familiar.
it may be korean - pos samsung.

leaning over "o" symbol is definitely Nichicon, look at the datasheet linked to in post#2