When a Computer System Won't Boot

When troubleshooting a system that won’t boot, always try unplugging all ribbon cables and removing memory sticks and all expansion cards. Boot the machine. You should get the correct beep codes your version of BIOS issues when it detects no memory.

  1. Did you get the beep codes? Yes, move on to the next step. No? It’s a bad CPU. Try a known good one.

  2. If you get the beeps, next insert the memory sticks, one at a time, rebooting after each one. If you can install all memory with no memory-related beep codes, move on to step three. If not, replace the memory.

  3. Once the video card was in place did you get the beep code standard for adding the video card? If yes, add the video card. If no, consider replacing your motherboard, because you should have. If you got the beeps, add the video card and reboot. If you get the same beep codes with the video card installed as without, your video card is bad. Replace it. If the codes change, move on to the next step.

  4. Now add the floppy diskette drive cable. It’s pretty rare that the floppy drive prevents a system from booting, but to be consistent, start the machine again. There should be no difference from when you booted to good RAM.

  5. Add the IDE cables, one at a time, rebooting after each one, starting with the hard disk cable. Quite often, a hard disk failure won’t elicit beeps, even with a BIOS with beep codes programmed in for a hard disk failure. But the machine might simply come screeching to a halt. If this happens, or if you get beep codes indicating a failure, use the same cable to plug in the CD-ROM, assuming one is installed. If you get no error codes with the CD-ROM, replace the hard disk drive. If you get exactly the same error with the CD-ROM, your problem is either with cable or the motherboard. If this happens, go to Step 5. If you have no error code with the hard disk or the CD-ROM, skip to Step 6.

  6. Assuming the failure followed over to the CD-ROM, always try the easiest thing first. Swap out the IDE cable. Still got a problem? Swap out the motherboard.

  7. Now add the expansion cards. Expansion cards usually don't elicit beep codes. But when you get to the one that prevents the system from booting, you'll probably be able to pick up on that glaring issue.

  8. If all of the above failed, look up the tech support number for the manufacturer and give them a call. You did your part.