I installed a clean version of Windows XP Professional SP2 on my e-machine PC. Now I have no sound, its showing like I dont have a sound card or something. This computer has a " NVidia nForce MCP51 (430i) " chipset and device manager has a list is things with yellow question marks to the left. ??? Multimedia Audio Controller ??? SM Bus Controller ??? PCI Simple communications controller ??? Other pci bridge device im not sure what these other things are but im assuming my audio problems has something to do with the multimedia audio controller. ive tried the NVidia website to find what i need but i cant figure it out. can anyone help me with this?