ive heard that if you put a computers motherboard into a microwave it will make the entire thing blow up! has anyone else heard of this?

It can depend on the components but I believe they react the same way as metal and other circuit boards do in a microwave. i.e. they spark or melt.

the spark must be made by arching the metal components, but the explosion is what confuses me, is there any explosive parts to a computers motherboard, its not as if theres gun powder on there?!

quote:

is there any explosive parts to a computers motherboard

They don't explode, they spark and melt.

It may be possible for some of the chemicals found in capacitors in early motherboards to react violently to microwaves but I doubt it.