How Many Caps Should Be Replaced On The Average Motherboard??

[He's Dead Jim]

i have read many posts on here that say replace all the caps on the motherboard, but i have read just as many that say that just a few caps have been replaced....

i was wondering if there was any sort of standard, like only replace the power caps, or only replace the ones above a certain value, or for a particular circuit....

For example, in this thread:

https://www.badcaps.net/forum/showth...highlight=6312

there were nine caps replaced as shown in this picture....



but what about the other caps in this picture??



do they need replacing as well??

i have many boards here that have 30 or more electrolytic caps all over the board so i would like to be able to better assess if they are worth repairing or not.....

thanks...

[i4004]

Re: How Many Caps Should Be Replaced On The Average Motherboard??

>do they need replacing as well??

get esr meter, and you'll know...

if you're in usa, this is handy
http://www.anatekcorp.com/blueesr.htm

caps around the cpu are loaded more than these on other places.
but it can indeed be the case caps around the cpu are good, while others are shot...
it all depende on the quality of caps on particular location...

oh yeah, you have kits sold by owner of this site (badcaps.net) for some mobos...
see if his prices are acceptable to you
https://www.badcaps.net/pages.php?vid=21

[He's Dead Jim]

Re: How Many Caps Should Be Replaced On The Average Motherboard??

>do they need replacing as well??

get esr meter, and you'll know...

if you're in usa, this is handy
http://www.anatekcorp.com/blueesr.htm

caps around the cpu are loaded more than these on other places.
but it can indeed be the case caps around the cpu are good, while others are shot...
it all depende on the quality of caps on particular location...

oh yeah, you have kits sold by owner of this site (badcaps.net) for some mobos...
see if his prices are acceptable to you
https://www.badcaps.net/pages.php?vid=21

thanks for the quick reply...

my multimeter has a built in capacitance tester, so i'll re-read how to use it....

i usually my my replacement components from Mouser:

http://www.mouser.com/

i haven't had problems with them yet, plus i do a lot of work on older boards that aren't listed in the cap kit section...

thanks again...

[i4004]

Re: How Many Caps Should Be Replaced On The Average Motherboard??

capacitance is not the same as esr, and capacitance is not really a parameter you're interested in...

[He's Dead Jim]

Re: How Many Caps Should Be Replaced On The Average Motherboard??

capacitance is not the same as esr, and capacitance is not really a parameter you're interested in...

I'm reading up on esr as well...

[gdement]

Re: How Many Caps Should Be Replaced On The Average Motherboard??

The larger caps tend to be the ones that fail most of the time. Depending who you ask, some people like to replace anything down to 1000uF, or down to 470uF, or down to 330uF.
Another way to look at it is to replace anything with a vent.

Those are just general guidelines, you can adjust depending what you think of the particular brands or series of caps you find.

[He's Dead Jim]

Re: How Many Caps Should Be Replaced On The Average Motherboard??

The larger caps tend to be the ones that fail most of the time. Depending who you ask, some people like to replace anything down to 1000uF, or down to 470uF, or down to 330uF.
Another way to look at it is to replace anything with a vent.

Those are just general guidelines, you can adjust depending what you think of the particular brands or series of caps you find.

kool, thanks....

[themainproblem]

Re: How Many Caps Should Be Replaced On The Average Motherboard??

I realize this has probably been asked earlier. and there is so much information to wade through. But.... What is your favorite replacement cap and why? If I want to make this problem go away for 5 or 6 years or more what is your recommendation? Nichicon? Thank you. Mike Apache Junction AZ

[PCBONEZ]

Re: How Many Caps Should Be Replaced On The Average Motherboard??

It's not quite that simple.
Brand isn't the whole thing there is also the Series (or model) of that brand.
The series' are used to differentiate the various Grades.
There is also availability issues.
So, often availability in the needed grade overrides preference completely.
.
With a few exceptions Japanese brands of the right grade are the ones to choose.
.
The exceptions.
Chemicon KZG (and presumably KZJ because they use the same electrolyte) have problems whe too near heat. Not a good choice when other optiona are available.
Some (maybe all) Nichicon HN and HM series manufactured from 2001 thru 2004 were defective.
.

The reason for specifying Japanese brands:
A study done by the Universtity of Maryland showed that the aluminum foil used in caps available on the TW and CH markets is of sub-standard purity. The impurities eventually break down the electrolyte. (Failures are the same as that 'Stolen Electrolyte Formula' problem but it takes a bit longer to happen.)

Some TW and CH manufacturers may import the AL Foils from the US or Japan but there is no way to know for sure, so the save bet is to source caps from Japanese manufacturers.
Note: Some Japanese manufacturers do have facilities in TW and CH but they import their AL (and electrolyte) from their other facilities in Japan.
.
TW and CH should be extended to include Korea, Malaysia, and India.

There are few caps manufacturers in the US or Europe that make Low ESR caps and those that do are significantly over priced.
That's the other way we end up in Japan...
.

Now that I'm done with disclaimers:

I like Rubycon, Panasonic, and Sanyo when I can get them.
Then any of the other Japanese manufacturers.
[Chemicon, Nichicon, Elna, Hitano, NIC Components, and whoever I forgot.]
If I -HAVE TO- I'll get Samxon but I'm not sure if I fully trust them yet.
.

[Krankshaft]

Re: How Many Caps Should Be Replaced On The Average Motherboard??

If I -HAVE TO- I'll get Samxon but I'm not sure if I fully trust them yet.

When I ran into a rash of Gateway monitors with hatched Samxon GFs it kind of hurt their credibility with me personally.

First impressions with Chinese caps are lasting ones I'm afraid.

[Wizard]

Re: How Many Caps Should Be Replaced On The Average Motherboard??

Samxon GF are fakes. IIRC.

Cheers, Wizard

[PCBONEZ]

Re: How Many Caps Should Be Replaced On The Average Motherboard??

There may be fake Samxon GF but Samxon GF is a legit series.
.

[PCBONEZ]

Re: How Many Caps Should Be Replaced On The Average Motherboard??

i have read many posts on here that say replace all the caps on the motherboard, but i have read just as many that say that just a few caps have been replaced....

i was wondering if there was any sort of standard, like only replace the power caps, or only replace the ones above a certain value, or for a particular circuit....

Back to the start.

"How many" depends on what's there to start with.

"Which" has changed over time and varies by techs personal experience/preference.
-
Few years ago replacing everything 1000uF and up few problem size/brands (small 220-330uF Choyo, Stone, and Chhsi in sound for example) was pretty standard and a few problem brands.
-
Then the HN and HM problems started showing up and that included a lot of 820uF and a few 470-680uF that would blow, so the bottom end was lowered to 470uF by many techs.
-

-
My preference is to replace all crap brands with vents stamped into the top regardless of uF or physical size -and- any that are 6mm and larger.
That's probably over kill but it's usually not that many more caps and I'd rather replace a few extra caps than have to take down a system to pull the board out again.