Thanks for the help. I got it fitted but sadly when everything was put back together there was no fan spin-up after about 30mins racing. The heatsink was making the upper casing warm and I would have expected spin-up by then. Nothing. FFB, buttons everything else working perfectly.
I'm a moron when it comes to fan connections. I haven't played with one in about 10yrs. As the Noctua is a 3 pin and the T500rs has a 2 pin connector I bought the adapter below. I didn't know when I bought it that the 2-pin head is not the same type as the connector on the T500rs but I 'made it fit' with a bit of filing of the T500rs socket (nothing too destructive it is still connected to the mobo.
http://www.amazon.co.uk/gp/product/B003D6O53Q/?tag=gtplanetuk-20
As you can see it has black and yellow wires as opposed to the black and red on the original T500 fan but when the Noctua is connected to the adapter it connects
Noctua black - adapter black
Noctua red - adapter yellow
View attachment 202863
When the adapter connects to the T500 its black wire is where the red is on the original fan cable and the yellow is where the black would be on the original fan. Is the reason its not spinning up a polarity issue or has anyone any ideas.
Really appreciate any help. Thanks.