what psu do I need?

im also planning to use the raspberry pi B model

I would consider a cheap PC power supply as they will provide all t he power you need  for your monitor and easily power your PI plus any ancillary hardware required for the project. They can easily be got hold of, and are complete in their own case so you can build them in to your design with little problems ...They can be bought for under £10 in certain places!

I have one, but does it matter how much aps it puts out?

Well the PI needs 5V @ 500mA minimum, Monitor 12V @2.5A so if you use a linear regulator for the PI, thats 12V @ 3A + what ever else you add to the mix.

Please remember the PI will NOT use 12V, it would break it

Peter

I just thought the 12v 32A might blow the moniter

Hi Noah, The power supply puts out a voltage level, like 12 volts. The equipment that  you hook up to it will draw the amount of amps that it needs. All you have to verify is that you do not hook up more things than the maximum rating of the power supply. If you look on the power supply it will give you the Volts and the Amps but the amps are only telling you the max that the supply can handle. If the supply doesn't give you an amp rating then divide the watts by the volts and this will be the max amps.

John

thanks a lot. you have really helped me a lot!

Actually, from a theoretical point-of-view current and voltage are "symmetrical" Anything that happens in one circuit with a current, you can make happen wtih a voltage in another circuit.

So it is perfectly possible to make a "12A, 32Vmax" powersupply. THAT one will definitively blow up your pi and display.

It just so happens that, as John says, it is more common on this planet to build/sell constant-voltage, variable current powersupplies. On the other hand, for powering leds, the constant current, variable (but maximized) voltage powersupplies are nowadays also available.

Ah ok. I see. Thanks for the help!

As you are in Australia, your local Jaycar might still have stock of a dual laptop type power supply - +12V @ 2A and 5V @ 2A.

I realise the current output is not optimal for either the screen or the Pi, but your monitor may not actually require a full 30W, you would need to measure its current draw.

Of course if electronics is your 'thing' then building your own is not that far out if reach. If you are not knowledgeable enough to play with the mains side of a power supply, you could always make the DC side, and purchase an adapter that puts out 15 or 18V at approx 1 - 3A (the current required would depend on whether you are making a linear or switchmode DC to DC converter).

The only thing I would point out, is that with many computer PSU, only one rail is actually voltage regulated, normally the 5V one.

Sadly, it would probably be more expensive than just buying a ready made unit.