Toshiba Satellite A305-S6872
A while ago I've seen on another forum a solution about replacing the NEC Tokin capacitor under the CPU socket to solve that common problem.
Symptom: machine freezes or restarts when plugging the power adapter.
Solution: replacement of the NEC Tokin capacitor under the CPU socket.
The fact is that it's not always possible to replace the capacitor for the same (here in Brazil it is very hard to find, for example).
The original NEC Tokin capacitor on this machine is 900 uF 2.5v, so it's possible to replace it using normal capacitors in paralel.
I recently fixed a Toshiba Satellite A305-S6872 and had the opportunity to take some pictures to show how to place the capacitors. In that case I ended up with an equivalent of a 1320 uF 2.5v capacitor, which is not bad at all.
4 X 330uF 2.5v in paralel:
Конденсаторная сборка NEC 900uF, 2.5v - замена на 4x330uF, 2.5v.jpg
That solution was also successfully applied to an Acer Aspire 4746z with the same problem.
Hope it helps.
Note: I decided to keep this message in English because translators are not very good yet. Please, tell me if this is against the forum rules.