If you have onboard sound go into the Bios and disable it, let the computer boot then switch it off.
Get the lid off and install the card in a free pci slot (make sure you pull the power lead)...get the lid back on and boot up the computer.
Windoze should see the card and ask for the driver disk...insert and follow the onscreen instructions.
If you have some other sound card in you are replacing, got to device manager, right click on your sound device and REMOVE it. Shut down, pull the old card, reboot, shut down, instal the 44 as above
Good luck, it's really easy