hey all i have a p3 1.13 on an intel "d815egew" mother board and have a 512mb ram stick wich is pc100 but the mother board reads it as 256mb

??? i dont know how to change this ?? i checked my bios and is sais that the fsb speed is 133, and i can't change that via my bios. if i change the fsb speed to 100 will it work ?? the max ram the board can take is 512mb.
another problem i have is my internet (on win xp) ramdomly cuts of and on, only for seconds at a time.. ?? i am using a cable modem and a lan network. scanned for viruses and nothing, adware,spyware ect. i've read heaps on articled where you guys have helped people out, please help me.
thanx in advnace
marty.