On 3 Feb 2005 08:22:50 -0800, (purtnoy) wrote:

Just replaced all the 2700 micr 6.3 volts, with 3300 mic 16 volt caps
(the 3300 caps are twice as big around,(does that matter?)

Yes. In this case it does matter.
In lineair systems, 'bigger is always better'. On your
motherboard exceeding a capacity value by 50% could disrupt the
entire regulator circuit.
Basic operation in this case is based on energy stored in an
inductor, periodically transferred via a (schottkey)diode into a
low ESR capacitor.

You can only replace those capacitors with types of roughly the
same value, high temperature types and --at least as important--
low ESR values.

had to
solder longer legs to raise them up, so they can fit without shorting
them out.

That also is unacceptable. This will introduce an extra induction
('coil') in series with the capacitor. Take a look at the coils
surrounding those capacitors. And notice that they only have a
few turns, hence very low inductance :-)

The circuit you are working on is likely to be the CPU stepdown
regulator. That is a circuit that transforms 12 volts into
something like 1.55 ... 2.55 volt. At several amperes.

--
Kind regards,
Gerard Bok