Abit KA7 with bad NICHICON caps

[Topcat]

KA7 with bad caps, no surprise....

However, this one was recapped by someone else using Nichicon and Teapo caps.... Surprisingly, the Nichocons were bloated and bad as well as the Teapos...





I recapped it with Rubycon 10v caps instead of 6.3v caps, and it now runs perfectly... It hopefully it lives a bit longer... The only possible explaination for the failed Nichicons would be that the board was in a case with little to no ventilation, and they overheated. The caps by the CPU slot do get very hot under normal operation.

[kc8adu]

were the nichicons low esr?
strange.

[Topcat]

They're not marked 'low ESR', although, I've never seen a Nichicon that was. The caps are marked:

Nichicon
1500uF
6.3v
105*
HD(M) series

The guy sent me 2 KA7's, one had the vented nichicons and the other had the stock JPCON caps (vented of course). Both boards have been running for 2 days now, no problems since recapping.

[strife667]

bad nichicons

OMG, and I just recapped my Shuttle AK31 with similar Nichicon caps (1500uF, 10V, HE(M) model) :o

[willawake]

That array of Rubies is a work of art.

[kc8adu]

i have seen nichicons bulging/leaking in gm/bose speaker amp boards.
85c caps in a black on black vette?
no wonder they died!

[strife667]

Nichicon
1500uF
6.3v
105*
HD(M) series

just wondering... they used 6.3v caps to replace the old ones, were the original rated 6.3v or 10v? can this difference have some influence in endurance?

[Topcat]

That array of Rubies is a work of art.

Thanks! I FINALLY found a vendor with quality Rubycon 8mm caps, after a year of hunting. It looks a lot more professional than the 10mm rebuilds!

just wondering... they used 6.3v caps to replace the old ones, were the original rated 6.3v or 10v? can this difference have some influence in endurance?

The 10v caps can simply endure 3.7v more than a 6.3v. The temperature limitations and tolerances are the same. If the 6.3v caps were pushed close to their limits on voltage, using 10v caps might extend the lifespan. With the failed Nichicons in the KA7 above, I personally think they had overheated due to lack of ventilation in the case. Failing Nichicon caps is not a common thing.

i have seen nichicons bulging/leaking in gm/bose speaker amp boards.
85c caps in a black on black vette?
no wonder they died!

I've seen the same vented Nichicon 85* caps in Bose amplifiers in Nissan 300ZX's. You'd think a company with the reputation of Bose would use higher rated caps.

[flobot]

i also have an abit ka7-100
caps, also leaking... they are all JPCON
but i noticed that on the image above, (the first one) the taller caps pictured in the group of 4, are rated at 1500uF, while the ones on my board are rated at 2200uF, ive already replaced all of my 2200uFs with new ones, as they showed the most bulging and leaking..

and another next to the dimm slots (the outside edge right in the middle below two other 2200uF caps)

my question is then should i have replaced the 8 caps that were 2200uF before with 1500uF ones?

i also ask this because i noticed that the replacement cap kit from the main site contains no 2200uF caps whatsoever but 24 1500s

hmm bad move? guess i found this site a bit late... though i doubt you ship to europe...

i just bought these caps at my local electronics shop, cant really tell if they even have a brand name, they have 'NA' where the name is usually located

[bushytails]

Using oversized (in terms of microfarads) caps is OK, and in fact improves stability on some boards.

--Randy

[flobot]

ok... well i just want to be sure, i thought that uF values shouldnt be changed.. that only voltage could be (higher that is)...

also should i replace all the 1500uF caps? most 'seem' ok... there were only 2 that were leaking, granted the others could still be bad...

one other question. which two 1000uF caps would be the ones replaced by the ones included in the set?, i noticed that only two 1000s are included. but theres more than that on the board