SuperDot Motherboard Recap Repopped Caps

[dhamrin]

Just finished recapping a SuperDot Motherboard. After successful power up, it re-blew the exact 2 same caps which were visibly popped in the first place. See attached picture with finger pointing to the 2 bad caps (Sanyo 6.3V, 1000mf). There were about 15 of these on the board, all but 2 of which I replaced even though they looked fine. Any ideas what I should try next? This is the first time I have had this type of problem. Thanks to anyone who has seen this before and can help.

[Pentium4]

Re: SuperDot Motherboard Recap Repopped Caps

Those don't really look like Sanyo caps. Did you buy them new or resuse old ones?

[mariushm]

Re: SuperDot Motherboard Recap Repopped Caps

It's Supermicro, not superdot.

Those don't look like Sanyo capacitors.

Check the voltage on those capacitors that are swollen.

check your 3.3v and 5v from the power supply

check those dpak (to-263) ICs they may be shorted or overheating causing problems.

[mockingbird]

Re: SuperDot Motherboard Recap Repopped Caps

Those look like OST to me...

Check your power supply as well... RAM is either taking voltage from the 12V/5V rail and regulating it down to 3.3v or straight from the 3.3V rail. Check the secondary caps in your PSU.

[RJARRRPCGP]

Re: SuperDot Motherboard Recap Repopped Caps

Some SuperMicro boards may just be re-badged stuff!

One that I saw looked no better than some $45 POS. Would make Topcat cry!

[mockingbird]

Re: SuperDot Motherboard Recap Repopped Caps

Motherboards are motherboards nowaday... Aside from the quality of the caps and FETs, they all revolve around fairly mature BIOS implementations and standardized chipsets with unified driver architectures. Not like back in the 80s when you had to take ROM chips back to the distributor to get flashed to fix some major errata.

[dhamrin]

Re: SuperDot Motherboard Recap Repopped Caps

Bad wording on my part. Originals were Sanyos 6.3v 1000mf 8x14mm, replaced them with new Nichicon 8x15mm and a few 8x13mm of another brand (board not with me at moment). Which was another question I had: How much does height of a cap matter? I usually try to match exact dimensions, but I was in a jam and substituted a few 13mm tall caps for the 14mm originals as noted above.

Thanks guys for the ideas on what to check next.

[lti]

Re: SuperDot Motherboard Recap Repopped Caps

There are a lot of caps that appear to be installed backward. It looks like the shaded section under the cap should be negative, but the positive lead of most of the black caps is on the shaded side.

[momaka]

Re: SuperDot Motherboard Recap Repopped Caps

How much does height of a cap matter?

It almost never matters. As long as you match the specs of the new caps to the old ones (i.e. capacitance, voltage, ESR, and ripple current), then all should be fine.

Any ideas what I should try next?

Post some more pictures of the area where the 2 bulged caps are. It looks to me as if the MOSFET next to them is damaged, but I can't tell for sure.

[c_hegge]

Re: SuperDot Motherboard Recap Repopped Caps

There are a lot of caps that appear to be installed backward. It looks like the shaded section under the cap should be negative, but the positive lead of most of the black caps is on the shaded side.

Agreed. Those are definitely reverse-polarised. Re-recap it and put the caps in the right way.

Out of curiosity, why did you replace the original Sanyos? They are a very reliable cap manufacturer, and shouldn't have failed.

[Topcat]

Re: SuperDot Motherboard Recap Repopped Caps

umm, the popped cap is in backward.

[ben7]

Re: SuperDot Motherboard Recap Repopped Caps

There are a lot of caps that appear to be installed backward. It looks like the shaded section under the cap should be negative, but the positive lead of most of the black caps is on the shaded side.

I agree too.

[momaka]

Re: SuperDot Motherboard Recap Repopped Caps

There are a lot of caps that appear to be installed backward.

Good catch.
I think I have done one too many ASUS and old AsRock motherboard recaps .

[c_hegge]

Re: SuperDot Motherboard Recap Repopped Caps

^
Same here. I've done it to all but 1 or 2 of my ASUS boards.