Your vertical lines may point to a memory problem with the video card. If you have a chance to install a different one you may be able to report further about the process.
Pending on what type of motherboard you have, as it was answered allready, the new ram module may not fit into the system. Do you have the right speed, is this speed matching the Bios setup, what speed was the old one....
Also, under MY COMPUTER - SYSTEM you may be able to find interfering devices such as your SCSI with the VGA/SVGA or whatever you have, the soundcard may be involved as well.
Check for conflicts.
If you run W98 you have a utility on your CD called Dr. Watson, try to locate errors and conflicts with this program.