wrote:

On Feb 18, 6:20Â*pm, Jerry Peters wrote:
In sci.electronics.repair wrote:
On Feb 18, 1:09Â*am, jakdedert wrote:
Conor wrote:
In article , Rich
Webb says...

Perhaps the plague? No, not THAT one, THIS one:
http://en.wikipedia.org/wiki/Capacitor_plague

Worth eyeballing since you already have the main board exposed.

Didn't think laptops used electrolytic capacitors...

They're surface mount, so you might not recognize them. Â*Google is
your friend....

Yes, but, although surface mount caps can be electrolytic, in a
notebook (none at all if it's a good design), very few caps are
electrolytic, if any, except in the external brick AC-DC PSU.

That's complete nonsense, of course a laptop uses electrolytics, and
lots of them to filter power throughout the unit. As jakedart said
they're surface mount units. Take one apart sometime & look.

Jerry

I have, several times. They use mostly if not entirely solid,
(usually chip) caps, and ceramics with good reason. Electrolytics
wear out too fast inside modern laptops because of the elevated temps,
not to mention their height being a problem when engineering something
as thin as reasonably possible.

Here's a picture of both sides of a quite typical HP laptop mainboard,
under two years old and quite similar to what they're still using.
Point out the electrolytic caps on it and BTW, this is the whole thing
there is no separate power board:

http://img242.imageshack.us/img242/5075/topsmfz3.jpg

There are six visible in fz3.jpg

http://img243.imageshack.us/img243/961/bottomsmsf5.jpg

and four, possibly five in sf5.jpg

The solid caps are black, and yellow.

Those two are tants and I think the others are too !

The ceramics of course are tan.
There are plenty more pictures from 3rd parties available with a
google search if you can't accept the above pics are typical:
http://images.google.com/images?q=laptop+mainboard

--
Best Regards:
Baron.