I have one laptop D630, it’s a very good laptop and with high performance.
Recently the power button started to fail and now does not work at all, I guess it’s the rubber conductive switch that’s located below the power button. For the moment, since I don’t find the exact cause of the failure and its remedy, I’m using it normally by the help of the docking station (this saved my life!) . With the docking station I’m able to switch it on, by other side there’s a lot of extra connections there (serial, parallel, mouse, kbd, extra usb, etc)