So I recently created a home office. My primary rig is a really old Dell Inspiron 9100 laptop, 2.4Ghz P4 and I have dual monitors attached to it - a 24" and a 22". I also have an NAS. Both are on about 10~ hours a day, most of the week. My power bill just DOUBLED from ~$30 per month to over $70. I've been looking at a new rig anyway, so would a newer desktop, even though it would be more powerful, consume less energy than this old P4 I'm using? Would it make any difference at all in my bill? No other changes have been made, so clearly the computer is the culprit for the costs.