Do I need a new PSU or just new connectors?

Hey guys

In the long process of restoring an old system, I think I know what is causing all my problems. Half my big connector went through the deep fryer... not really but you get the idea

http://i.imgur.com/pnVgyRl.jpg

My system is a 2008 alienware aurora series desktop and uses 700W power supply. I don't know much about these so I wanna know ;

1. Do I need to buy a new one? or...
2. Do I need to get a new set of wires?

I dunno if you can just crack it open and insert new wires easily...
Are there any guides on that?

Any help is appreciated, I will try to supply any additional info about the system if needed

 
Solution
thats why u never buy alienware, buy power cyber power or rebuilds in general, they cheap out on the motherboard and the power supply.

try first if your mobo works with another power supply.
What happened the day this PC went down was my brother was using it in an already hot room for multiple hours straight (genius idea, I know) when he got a blue screen and the power button would no longer turn on the system. (Had to make a switch for it instead, which is how can power on now)

There was no fire, at least from what I can tell. The motherboard looks like it's in good shape. I don't see any signs of burns on the female end of the connector, not on the board either.

I remember the question I was gonna ask about power supplies. Are they all mostly the same size? Do I need to get the dimensions of the current one so I can get a good fit? Any info on that would be appreciated.