That one is not for direct cooling of the GPU. It is just another exhaust fan for your case. That one is so small the benefits don't even seem worth it.
Something like this may help but is only fans over your GPU not blowing any air out of the case.http://www.newegg.com/Product/Product.aspx?Item=N82E16835888112
Although I still wouldn't expect the GPU temps to improve all that much.