Prolinea Running Win95

TRying to upgrade a compaq prolinea running win95 with a 600M hard drive to win98. I’ve tried everything from replacing the har drive with a 2G. loading 98 on another machine and installing the drive back into the original machine. I continue getting disk errors and at other times the machine doesn’t even see the hard drive I’ve formatted and partioned the original hard drive and tried to load win98 with the cd. pc will not allow me to break into bios to change my boot device to the cd rom. Can anyone give me some suggestions?