Omaha, no matter what, leave the receiver on the 8 ohm setting. Any other will limit the amount of power it can put out. Unless you have a cavernous room and consistently listen at rock concert levels, the Onkyo should be fine. I've read it does run hot, so be aware of enough venting space for it.

Also, yes, you can run a separate amp to power your front speakers and let the Onkyo handle the rest. The amp hooks up to the receiver's pre-outs.

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"Nothin' up my sleeve. . ." --Bullwinkle J. Moose