Sorry, newbish question from a newbish guy

Tried searching with no luck.
My background in guitar amplification tells me that if I turn on a tube amp with no load (speaker) hooked up I run the risk of harming the amp. Is this the case with solid state amps, as in home theater amps?
Bottom line, can I hook up a surround type amp with only the L/R speakers or just L/C/R speakers connected or will I damage the amp since there is no load on the surround outs?
Thanks everybody! You all rock