I haven't heard of an Asus nforce board that uses Realtek as the sound chip. If you can show me a link, I'll appreciate it. The A7N266 used the C-media, the rest, like A7N266-VM, A7N266E and C all use the nforce APU. You may have either confused the Realtek with the LAN chip or with the codec that some boards use. Epox uses a Realtek codec in conjunction with the nforce APU in their newer nforce2 boards but that doesn't mean the sound is now based on Realtek.