Mem. module help

[moparmanpr]

Hello,i've installed 2-512MB modules in a dell dimension2300. the message i get is:"warning, memory size is changed
F1 to continue
F2 setuup
F12 boot menu
F10 utility mode.
i chose F1 and received:windows could not start because the following file is missing or corrupt: System32\DRIVERS\pci.sys
help!

 

[mosox]

Do you have this issue with one stick of RAM?