I have the same problem, only DC never worked on my PC at all. I have a Gigabyte 8IK1100 Rev 1.0 and 2 Kingston 512MB PC3200 sticks. I thought that if they matched they would run dual channel. Am I right? They don't. All my system does is beep nonstop as soon as the power is turned on. I can run both sticks fine in single channel though.
Now, I am using Kingston ValueRam, does that matter?