See whether the heat sinker is dust free , or not.  the power box/smps(if desktop), . if laptop, see whether the tracts are dust free, from where the air is blown out. also check whether any plactis or rubber coated wire is in contact with heat sinker or processor...

Brand new machine?

Sometimes it needs breaking in, but if the smell persists after a month or two, have it serviced.

Something like "new car smell"??

That is uncured plastic which will subside with time, if a normal occurrence.