Quote from: mrhobbeys on October 02, 2011, 04:23:37 AM

Interesting points, but I think still having a machine running solo specifically for the variance is a good thing because if I hit I suddenly can afford to buy some new hardware that I would not otherwise have. And if you read before I am a gambler ;-) I used to play online poker for a living now I am doing actual working and looking for a new way out.

As an update what I thought was a 5870 turned out to be a dead card so now I have my 6450 mining on this computer @ 28.5 Mhash/s on a pool. It is the best working machine I have atm so I am thinking of putting this solo and switching all the others to a pool. Right now I am paying $0.08 per KWh and according to my power management software I am using 5.40 KWh per day.. I also have a Quadro 3xxx that is PCIe that may be dead. Worth using if it is not?

Its not profitable if you count all 225W of the machine (ie, if you otherwise turn the machine off).
Power cost per 24h: 0.43 USD
Revenue per day: 0.09 USD
... less power costs: -0.35 USD

See for yourself here:
http://bitcoinx.com/profit/index.php

Dont bother with the quadro either.
There are only a few cards out there where its even possible to be profitable, that is basically 5770s, 58x0, 59x0, 68x0 and 69x0 cards. Even with those cards its tough to make a profit, with anything else, forget it.