PC Totally Freezing

[Lisa-32-UK]

Hi guys, my computer has been working fine for about 6 months since I built it, however last week it totally crashed, I was unable to turn it off by the button, the keyboard would not do anything, the mouse would not move, after switching it off at the mains and leaving it half an hour it still wouldn't work, I took the side off and unplugged everything, put it back together, then it worked again until last night, same thing happened, totally crashed, no mouse movement.
This time I couldn't get it to come back on at all, so I decided to inspect all the wires which I have and I found a cable with connectors that converts 4 pins on the PSU into a 8 pin socket on the motherboard... the yellow wires were melted, I took it off and plugged the 4 pin directly onto the motherboard and its currently working,

3 questions for you guys

1 - Would the melted wires cause it to crash??
2 - Am I causing damage to the motherboard by having a 4 pin connector on a 8 pin socket??
3 - Could the wires melting have caused any other damage to the parts?? (everything inside if under guarantee)

I've added a list of what the system is made up of below,
Thanks Lisa,

Asus Sabertooth 990FX,
AMD FX8350,
700W PSU,
3TB HDD,
2TB HDD,
BLU RAY Writer,
DVD Writer,
8GB DDR3,
Xilence M606 Dual Fan CPU Cooler,
Windows 8.1,
6 X 120MM Xilence Fans,

 

[dark_lord69]

Would the melted wires cause it to crash?? - Yes, you computer could be experiening an electrical problem.

Am I causing damage to the motherboard by having a 4 pin connector on a 8 pin socket?? - Typically not... Most motherboard manuals will say 8 OR 4 pin connector.

Could the wires melting have caused any other damage to the parts?? (everything inside if under guarantee) - It's possible but not likely if you aren't experiencing issues... on the other hand you said you ARE experiencing issues so.. some part(s) could be damaged.

I would disconnect any PCI or other components that aren't 100% nessary for booting the computer. Then see how things go, if it's still an issue I would start by runing a memtest for a day or two.