audio issues with vista 64bit

finally finished my computer to some degree and have installed COD4 on it plays well graphics maximum. brilliant.

but the sound just cuts out half way through.

now ive tried changing certain things stuff like that but because its not connected to the internet i cannot update drivers easily. does 64bit vista come with direct X 10.1???

or is it a game patch i need to download?

im using the onboard audio card built into my keyboard which the and ENERMAX. this all works perfectly on my other dell. but when i move it to my better computer it cuts out half way through a COD4 mission.

other issues are that the mouse wont work if i restart the computer i have to take it out the back usb and move it to another one to get it to work. my mous is a RAZER LACHESIS.

yet again this works on my other computer but this might be because i havent installed the software that comes with it onto my dell. or it might be that it is allways on because im using an externally powered USB port extension.

any help will be greatfully received!!!!

thanks

jason.