Quote from: mrjones on April 16, 2011, 07:24:37 PM

Quote from: theSteve on April 16, 2011, 06:56:16 PM

I have 45 pc's running 24/7, all connected to the internet. They are used for automation processes, and I access most of them using remote-access software.
- They're all running Windows XP (and need to remain that way)
- Most of them are intel p4's running at 2.8 ghz.
- Some of them have video cards installed, but nothing newer than 3 years old.

I've read that CPU mining is no longer profitable.... but I'm searching for a way to monetize the spare CPU time.

Any thoughts?

Forget it. A 2.8 GHz Pentium 4 will only achieve around 1.12 million hashes per second. All 45 computers, together, will be around 50 million per second. You're not using spare CPU time; you'll instead be running all of those computers at full power 24/7, which is roughly an extra 70 watts each. So 3150 watts to produce 50 million hashes per second.

At the current bitcoin difficulty, it would take you around 12 weeks to generate 50 bitcoins (and that's assuming difficulty doesn't increase, which is unlikely). 12 weeks * 3150 watts = 6300 kilowatt hours of electicity. At average US residential rates (~$0.11/kilowatt hour), that's around $700 of electricity to generate 50 bitcoins which may be worth roughly $40. (Plus don't forget about the added wear and tear on the computers and the extra heat they'll be generating, and all of the fans that will be running at full speed all the time.)

By comparison, a single 5970 video card will use 300 watts to generate 600+ million hashes per second. That is 12 times faster with 10.5 times less power, or 126 times more efficient.

So ... no.

He did NOT ask what would be better
he stated he has 45 machines that already run 24/7
Guess YOU CAN't read (or is the problem comprehension)

I'd suggest slush's pool with puddinpops rpc miner on each machine