Computer starts to get slow as soon as the charger is plugged in

Hi everyone!

I have a small problem that occurs from now and then. Sometimes (about 80% of the times) when I plug in my charger into the computer it is starting to get "slow" i.e the dock takes time to show up, can't move a window without the computer lagging as h*ll, scrolling is impossible and so on. When I look at the processes it seems that there's no software eating all the resources from the cpu, instead I am starting to believe it might be something between the switching between the integrated and discrete graphics card. I've been using the gfxCardStatus (http://codykrieger.com/gfxCardStatus) for a while and it looks like the software is doing something wrong. Tried to uninstall (using CleanApp) but the problem still occurs. Anyone else experiencing the same problem that might have a clue to solve it? Done a couple of PRAM restets but the problem still occurs.