I've been wondering about providing power to my 12v cameras and some alternative approaches.

Since my system is a DVR card in a computer, and my computer has a 500W power supply, would it be feasible to power the cameras from the power supply in the computer?

Has anyone ever tried this?

I had also considered using an extra computer power supply unit to power the cameras. I have several of those laying around

Pro's wouldn't do it. But others have done it. Check out this thread on the subject:

http://www.cctvforum.com/viewtopic.php?p=72212#72212

Thanks for the link, I should have known it had already been covered here.

Glad to help. The thread was kinda hard to find. The only way I found it was I remembered the discussion.