Laptop power supply trips Home Circuit Breaker

I've done a few checks on this and most responses concerning this problem suggest the power is on the blink. But this has happened with a Lenovo, Acer and Dell (we're not very loyal in our family :-) ), all new machines. One power supply - an old Lenovo one which got run over by a car and still works! - has never tripped it, the rest all have.

My conclusion from that is that it isn't the individual power supply, but is some feature of the way power supplies work. The breaker, I believe, works on checking for leakage to earth by comparing input and output voltage; so do modern power supplies have some intrinsic internal storage that causes a momentary difference between the two?

It can happen whether the laptop is connected to power supply or not; so, again, conclusion is that it isn't the laptop itself that is the problem.

I'm looking for a generic fix so I don't have to reset all the clocks in the house every morning after I start work.