Lets get the obvious out of the way, you're sure you have a sound chip in that computer? Modern motherboards are more likely to incorporate an onboard sound chip, rather than a full fledged sound card. You can easily tell this by looking to see where the sound output is on the back. If the sound output plug is on the backplane section of the computer (near where your rear USB ports are, or onboard networking) then you most likely have a onboard sound processor. If the sound output comes from a rear connecter shield that is offset slightly from the rest of the IO ports, then you have a true-to-form sound card. There is the slight possibility that you have a server motherboard in that system, which usually do no have luxury consumer items like sound support, but I highly doubt it.
Onboard sound has always been a PITA for me, as I've had some systems that have had completely disastrous support, and frequently I'd be happy to get it into an emulation mode, so that I could have at least basic sound IO. Open the control panel --> sound --> playback devices.
Let's see what you have going for you here, before you blame MultiPSK
