Audio Driver help in Vista

Ok so I had installed Windows Vista on a pc of mine, and I cannont get the sound card to install right, I am using a DIAMOND Xtreme XS51 , I know its a diamond and its kind of hit and miss, but I have xhausted all my known resources and tried various ways to install the drivers and yes I did got to the makers website and downloaded it, from there I even used the 7.1 drivers since a review stated they used those and it worked fine since the 5.1 drivers didnt, so I am asking for alot of help, I have been tinkering with this computer for three weeks making it stable since it wasnt and now I am running into a problem that shouldnt be this difficult. And yes all the drivers I have downloaded were for VISTA.