I have a ASUS TUSI-M motherboard, which has a AMR slot. What is the purpose of the AMR slot? Will an AMR card for that slot yield better audio performance than the on-board Cmedia 8738 PCI Audio Chipset? I also have a Sound Blaster PCI128 card from an old computer which I can install. Will the SB yield better overall audio performance than either the AMR Card or the Cmedia Chipset?