Power Supply Turns On Computer

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Jan 25, 2014
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Alright so let's see if anyone can help me here.

I have a buddy who lives in South Carolina at the moment and he's trying to replace a bunch of parts... the only problem is that he's not all too skilled in assembling a computer, which leaves me to helping him over Skype.

Now let's skip to the part where he has it assembled and he turns it on... problem is, He switches the switch on the power supply and it immediately turns on the computer without him hitting the power button and then all the fans on his computer just start getting as loud as they can. I'm not quite sure why this is happening and I'm wondering if anyone else here knows cause I don't quite honestly know myself.

Here's what he replaced and has:

Motherboard is a GIGABYTE GA-H61M-USB3H Micro-ATX: http://www.newegg.com/Product/Product.aspx?Item=N82E16813128589

CPU is a i5-3470: http://www.newegg.com/Product/Product.aspx?Item=N82E16819115234

The case is very old and is a SR5050NX COMPAQ Case