First you cannot auto shutdown without a compattable power box (Internal where your main power wire plugs to your computer.) If you have onw with a switch it should auto shutdown. This is called a ATX power box. You may have the other type AT which only the power plugs in. You can check by Pressing the power button. If it offs instantly, you have a AT power box. If you have to wait a few seconds, it is ATX. The diffrence is that AT powerboxes are in control of the power and with ATX the motherboard is. If you have a AT power box you will have to change it to an ATX on. (I advise to ask a computer shop) Your motherboard may not support both so you may have to buy another one (Basicaly byeing a new computer and it isnt worth it ) If your motherboard can take it to a computer shop to get it done (about £80 Just the Power Box) or you can do it your self if you know how to.
