Ok need some help, my dad has asked me to have a look at his pc, because my mum told him it wont turn on, ive tried all the plugs and everything, a little while ago it would login but freeze, any ideas?

So it freezes and locks up or wont even post (wont power on at all)?

Your a little vauge.

• is the powerplug connected to both wall outlet and PC?
  
• is the power button connected to the mainboard? (friend of mine forgot it once )
  
• does the inside of the pc smell like burnt material?
  
• is the inside of the pc pitch black in some places where it shouldn't be that way?

Beyond looking for loose wires and such, it is difficult to diagnose those kinds of problems without access to known good spare parts for testing.  The first thing I'd do to a computer that won't turn on is try another power supply, but you really don't want to buy one not knowing whether that is the problem.

You may be better off taking it to a shop.

i think you are best off taking it to a shop, my laptop did excatly the same thing as your dad's computer has. i phoned up dell and they came out and gave me a new motherboard and fitted it all for free. so possibly its the same thing, try taking it to a shop and see what they say, but ask how much it should cost before you let them do it as i am sure most will take advantage and go on and say yes well i did this that and the next thing, so beware!

hope you get it fixed!

I think what may have happened is that the hard drive has less memory than ever, if it frezzed.

If it did not turn on you may have to buy a power bar, (You can buy them at any hard ware store for a cheap price)

if your computer only turns on sometimes the motor tube might be popped, so you might have to go to your store where you first bought it and make them have a look at it.