I reformated my HD and re-installed WIN98. Every thing ran for one day OK. Today I set computer finally on the desk with the modem connection, printer and ZIP drive and it did not start. The power supply works, the HD and CD-drive spin but the PC can not deliver signal to the monitor and the system does not start up to the point I can boot from the floppy or pressing DEL change the BIOS content. I checked the keyboard because I was told if it is not connected, the PC does not start. The keyboard works fine with other computer. Still the connector to the motherboard can be the problem. The motherboard is the PC100 systemboard Slot 1 M741LMR. Any suggestions? I did not try yet to clear the CMOS memory and re-install BIOS. Thank you

You say it ran OK for a day. Did you re-boot any times during that day after you had the system working? Is that zip drive internal?

I had the same problem too when I got my new computer. I finally got it started and OS installed and everything worked until I started adding stuff like new CD drives, extra HD, and other components. What I did was try changing cables around, ie. switching CD drives around on SCSI cable.. same with hard drives. Also it would probably help to disconnect the add-on's and once you get the system running again add one at a time and while system is running if possible (like USB connectings and etc)

Cpu may be shot, if u have a spare one use it and test. If not, motherboard may have died.

Thank you for all the answers. TO add more information to the response #1, we ran the PC for one day, turning ON/OFF, checking software, etc. The PC performed OK. the ZIP drive is external. now I disconected all the peripherial and left only the basics; keyboard, monitor and mouse, still did not start.

Try to clear the CMOS while unplugged from wall.

You still have those drivers installed for the extras. This happened to me when I installed a graphics card with the wrong driver. Try removing all, then reboot, reinstall OS. Or install a new video card.