Use a battery instead of a PSU (Desktop)

[offy]

So, for my robot project, I require some type of computer, such as a laptop or desktop. I am on a budget, so I was wondering if I could turn one of my old desktops into a laptop like thing. I just need to take the PSU out and put in a battery, or get something to power the PSU.

Any Ideas? I would like it to be under $75

PSU specs:
250 watt

[galannthegreat]

Computer motherboards need +5, +12, +3.3, -5, and -12 volts to operate (though -5 and -12 are uncommonly used).

Pico makes a little dc-dc converter that would easily operate off of a 12v battery, though it only outputs 150 watts, which shouldn't be a problem for a robot.
http://www.mini-box.com/picoPSU-150-XT

I myself am looking into using my mini-ITX computer as a robot controller, and I have a question for you, what are you going to use to interface your peripheral to your robot?

[offy]

well, the computer is mostly for processing. I am going to write a program in Processing to make it do color tracking, and other types of commands. The computer is only for processing stuff that is a pain to do on a microcontroller.

[dellagd]

Well if you plan on taking apart the Desktop anyway, see how much voltage/amps it draws. Hopefully its under 1. Go get a 12 volt battery and hook it up to a cheap inverter.
Also you can rearrange the componets of the computer as much as you want, just make sure they don't overheat.
Remember, they weren't designed to be in laptop form.

[galannthegreat]

Pico dc-dc converter is cheaper than many inverters that I've seen, choose what you want, but that's just my idea.

[dellagd]

I should read more

A 250 watt inverter would cost $50+