Well, it can.. That card was released in 97 or 98 with some driver updates in 98. However, when it was released, it was compatible with Windows 95 and 98 only. So..
You can try and put it in.. if it works and sounds better... great! If not, then stick with the realtekk chip. Most sound cards have those 3 ports and they are usually for your speakers, line in, and microphone. So this shouldn't really have anything to do with your realtek sounding better or worse since it only has the speaker port.