Alrighty I just bought a ATX12V PSU instead of a plain ATX. Can I use it on my ATX motherboard leaving the extra pins unconected. r do I need to use an adapter?

By ATX12V you mean 24pin ATX plug? If so you'll need an adaptor. If I'm talking about something completely different, then :shrug:

Yeap 24 pin.

Yeah you'll need an adaptor like this http://www.pccasegear.com/prod2690.htm

Any idea where I can get one?

At that place? Its an aussie store, shouldn't cost too much for shipping.

Cool Thanks

Why would you need to buy an adapter if your mobo doesn't need it. With Antec style PSU's you can actually split that connector off should your board not require it.

if the main power plug is a 20 + 4 plug you can just plug int he 20 pin portion.

however the very newest atx psu's (i think atx version 2.1) dont have a -5v circuit, which some older motherboards need and wont boot up. just something to be aware of.

My thermaltake PSU has 24 pins but you can still use it in a 20 pin motherboard by just not plugging in 4 pins.

Also one of my friends yumcha PSU's had the same option.