Depends... do you pay the electric bill yourself? If so, then sadly the answer is probably that you are paying more to run the PCs than you are generating in bitcoin. BUT, if you were going to run those PCs anyways, then really you are making out better by producing _some_ bitcoin in the process. OR, if someone else is footing the bill, then mine away my friend - PURE PROFIT! 
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Jon
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Jon
Hi,
do not forget, that someone will have to pay for the electricity, and a minig GPU will consume more power than an idle one...