PC power for Arduino

Do I take a old 5V PC power supply with Arduino + 5v?
Arduino Is toleran ce +5V - +/- 5% ?
Thank you.

Sure, I'm powering most of my projects using an ATX-supply.

Have a look here http://www.electronics-tutorials.ws/blog/convert-atx-psu-to-bench-supply.html

The supply needs to deliver some power to keep functioning, that's why the set up uses a high power resistor. If you don't have or want to buy such a resistor, just connect an old broken hard-drive, to achieve the same.

Arduino Is tolerance +5V - +/- 5% ?

At 16 MHz the ATmega328P can run on 3.78V to 6.0V.

Depending on which Arduino your are using, you could also just use a switching adapter.
I use a 12V one for testing - very handy.


FWIW if your Arduino has a DC Jack, the recommended input voltage is 7 - 12V.