Hi,

To give you some background, it's 5 years old and apart from a new graphics card everything is standard; i7 quad core processor, using a 2011 (I think) Intel x79 express motherboard and the standard master I/O board too. Anything you need to know further can be found here.

The problem I'm having at the minute is that the PC won't start, upon pressing the power button the fans spin for about a second and the whole thing powers Down again, pressing the power button again yields the same results over and over. I noticed a solid orange light above the master I/o boards power cable connector, after fiddling with both ends of the cable the light remains on and the computer won't start still. I've pressed the black button on the back of the power supply and everything starts up as it should and got the same result with the paperclip test everything seems fine except the orange light above the master I/o board and the fact the PC just won't start.

The only other thing I've changed recently is the water cooling system for the processor which I have replaced with a Corsair H60. Upon first installation and boot up everything was fine but when I turned it off and left it for an hour or so it wouldn't turn back on. now I'm stuck. 

Any advice would be greatly appreciated.

Thanks, Joe