I have an error I can't figure out.

[scrow79]

I am getting the message:"serial presence detect device data missing or inconclusive 100Mhz assumed" when I boot up. Everything seems to work fine but I still don't like it. Any suggestions?

[Underclocked]

Buy quality memory. But in the meantime you could set your bios memory settings to manual and select conservative (slower) values.
Is the memory labeled PC100 or are you trying to use non-pc100 with no SPD on the stick?