|You plugged a device demanding 1amp into a socket/source that can only deliver .5amp.|
It might well do so. I recall some min-tft screens/monitors delivered with psu mains adapters that were rated "well" below the current demands of the actual mini screens/displays. The adapters died in a very short time.
Does the laptop work otherwise?
Whenever I buy an external usb drive (HD/DVD) I get a dual usb/y-cable to allow me to power it from either two usb ports; or even better via an external mains adapter...; even if the usb device is allegedly OK with a single usb port or dual usb ports. Avoids the risk of your experience...
Is there per chance a replaceable fuse for the power board; or can that board be easily removed and replaced?
A phone call to a Toshiba might be worth a try - or at least an email - requesting advice re' changing the power board?