I just installed GTX 480 in a Dell Precision T7400 computer. Orignally I had a GTX 280 installed in it and everything was fine. After GTX 480 was installed, the soundmax card stopped working. In fact, it no longer shows up in the device manager. I don’t think I damaged the sound card or motherboard. Everything is working except for the sound card. I searched the Internet and saw that if I disable the Nvidia HD audio, the original sound card may come back. I tried this option and restarted the computer, but it still did not show the soundmax card. Please advise what I can do to bring the sound card back. The operating system is Windows XP 32 bit.