I have an ASUS P4B266-C mobo that I am running XP home on. It currently has 512MB of RAM (2X256MB) of PC2100. I'd like to upgrade the RAM to something more, but it has only two slots. The manual states that it runs PC2100 RAM. Can I install PC2700 RAM in its slots? Will the Mobo downclock them for me or do I need to set some BIOS setting? The ASUS support website has nothing on this. 