I am looking for a sub as I am upgrading my a/v receiver. My question is, can I use a sub that is meant for a pc or not? Is this the most ridiculous question ever?

Yea, it is. It is a pretty bad question. lol.

Computer subs don't have the right connections to get a signal from your receiver(subwoofer needs a line in). Also, you're really not going to want to use your computer sub, they have no comparison to a decent home theater sub. A real massacre. Try www.svsound.com or www.hsuresearch.com. They have some great budget subs. Or you could try finding a decent Velodyne sub on ebay. That would be my two cents.