The yellow question mark could mean you're trying to install the wrong driver for that particular sound chip.
Whatever the reason, we need more information -- either the make/model of your PC or motherboard.
Download and run Belarc Advisor from here:
http://www.belarc.com/free_download.html
Run it to create a list of all your hardware and software.
Post the list (minus the software details) in a new thread on the forum.
A new thread will ensure that someone will look at it.