Thanks for all of your replies!
the power/electricity consumed isn't really a concern for me, since it's included in my rent bill,
Well, you definitely would be profitable mining without any additional costs for electricity. The next question is, how much power can you consume before you have a.) issues with the heat generated (can you vent it outside?), and power capacity (how many amps before you are at 80% of the rated level for your circuits?
I don't think I would encounter any problem with the heat , since as I am based in Norway, and the average temperature outside where I live rarely goes over 12°C (53°F), I believe that it would be enough to just leave the nearest window halfway open, in the room I would designate to mining...
And as far as the power capacity goes, I don't really have any idea of what that may be, but I don't think that even the most power craving rigs would use up as much electricity as the 8x heaters [1500W/ea] I run during winter periods, along with the dishwashing machine (2000W), dryer (2800W),washing machine (1800W) and the electric stove (9800W).. [even though norway exports tons of gas, nothing is run by it strangely]
Anyway, I run into a deal the other day, where I managed to get 19 Lenovo workstations for free (they were throwing them away at the office), as per the pics below (some are missing from the image)http://d.pr/BL9q
All of them are running on Intel Core 2 Duo processors clocked at 1.80GHz, and have RAM ranging from 512 to 2048MB.
They all also seem to have a free PCIe slot, as per the following pictures:http://d.pr/UK5a
+ (full size img)http://img829.imageshack.us/img829/2531/img3210j.jpghttp://d.pr/32Po
+ (full size img)http://img42.imageshack.us/img42/6171/img3214j.jpg
And that's the really interesting thing, since I think that it would be quite easy to snap in some GPUs and beging mining without any additional cost..
So now comes the question.. What would the most cost-effective and profitable way to use these 19 workstations? What kind of graphic cards should I be looking for, to be compatible with them?
Thanks in advance again for any inputs...