Problems at startup

When starting my computer the screen shifts to the left and wraps to the right side. This does not cause a problem until I want to start in dos, view boot progress, or edit the bios. It is hard to read. This problem has been there since day one. Ilooked into the config.sys and the autoexec.bat to see if it gives any video settings and they don’t. Once the computer boots everything is fine. I have seen this before and could never figure out the problem.