0

One day while working on my PC, it suddenly hung with no response. I looked at the hard disk to ensure whether it's working but it failed - there was no blinking LED. I restarted my PC, my computer started but the boot screen was not showing up.

Do you think is it a BIOS, motherboard or processor problem?

1 Answer 1

6

Source Boot-up Troubleshooting Cookbook

Troubleshooting Boot Problems

1.0 BIOS Beep Codes
1.1 No Video Splash Screen
1.2 System Does Not Complete POST
1.3 Operating System not Found or Boot Device Missing
1.4 Keyboard Isn’t Recognized
1.5 Slave IDE Drive Not Detected (Hard Drive or CDROM)

1.0 BIOS Beep Codes

It is likely that the BIOS on your system was made by either Award or AMI. Today, the majority of motherboards purchased for upgrading come with an Award BIOS, though there are a very few that offer the AMI BIOS as an alternative. While Phoenix used to be very popular, it is now rarely found in desktop systems. Award became part of Phoenix in 1998.

The Award BIOS actually has only a single defined beep code, which is emitted when the video controller cannot be initialized. This code is a single beep, followed by three short ‘chirps’ in rapid succession. The short beeps can occur very fast, and might sound like only two, but by listening very carefully you should be able to discern three of them. If this signal is given, the video card may not be seated correctly, or it may actually be defective. If reseating it does not resolve the problem, try it in a different card slot (if available). As a final resort, the card may need to be replaced.

One other code that is usually given, but not officially defined by Award, is a single long beep that is repeated indefinitely. This generally is emitted when the memory refresh fails, which could be a bad connection, bad slot or a bad module. Once again, if reseating the memory modules does not correct the problem, try a different slot or replace the module.

AMI defines a number of beep codes, which are too numerous to mention. If you have an AMI BIOS, you can get most of the information you need from the AMI Homepage, under the ‘Tech Support’ section. More information about Award BIOS’, and additional technical information can be found on the Phoenix website. Other good resources for BIOS information are The PC Guide and Wim’s BIOS Page.

1.1 No Video Splash Screen

  • Check that the power cord is plugged into both the wall and the power supply (really!!). If the power supply fan doesn’t spin, either it is not plugged in, or the power supply is bad.
  • Check that the 12V power plugs from the power supply are properly plugged in. There are usually two plugs – P8 and P9. The two black wires on each plug should be next to each other (four black wires in a row). If this is the problem, the power supply fan will spin but the hard drive will not spin up.
  • Take out and reseat the CPU, Memory and Video card. If any one of these is not making good contact, the system will not boot. If you have your speaker connected, you will hear a beep code if this is your problem (check the documentation for your BIOS to interpret beep codes).
  • Make sure that your IDE cable (if installed) is connected with the colored edge (pin 1) aligned with pin 1 on the motherboard connector. If you don’t hear the hard drive spin up, that would be a good clue the cable is backwards.
  • Check the jumper settings for the CPU – both bus speed and clock multiplier. If this is set incorrectly, the system may not boot at all.
  • Make sure that there is no metal-to-metal contact between the board and the case, except at ‘designated’ points. This means that the small brass hex nuts that the board is held on with should NOT be used as a standoff if there is no corresponding hole for it. Doing this will cause a short between the board and the case, thereby keeping the system from getting the proper power, and possibly damaging the motherboard.
  • Check that you have filled the entire memory bank with memory. Pentium/Pentium Pro motherboards use two SIMMS of the same type (both 8MB or both 16MB), or one DIMM. They also must be in the same bank – which means they need to be right next to each other in even/odd slots (i.e., 0/1 or 2/3, not 0/2 or 1/2). Once again, check your motherboard manual for requirements in regards to which slots must be filled first, and how many slots make a bank.
  • If you didn’t do this first, take the motherboard completely out of the case (if you have it installed before trying to boot it) and put it onto a non-conductive surface (perhaps the top of the box it came in). Position it such that you can connect the power supply plugs, then insert the CPU, memory and video card. Give it one more ‘power on’ attempt. If it now boots, then you had some unknown contact with the case (grounded improperly). This step shouldn’t be too intrusive, as you were probably going to take it out and ship it back to the supplier anyways.

1.2 System Does Not Complete POST

  • Check that you don’t have mismatched memory in your SIMM slots. Remember, Pentiums require two SIMMs to make a full memory bank (but only one DIMM), and they must be like configuration (two 8MB or two 16MB, etc). Also consider that you may have a bad memory module if you are buying ‘generic’ modules. A good clue for this is if the system only counts up to 640K, then locks.
  • If your motherboard has cache on board (Socket 5 or 7), check that the L2 cache jumper (if applicable) is set properly. Again, read the manual. Note how much cache is soldered on board (if any), and how much is on any COAST module. Do NOT assume that you know how much cache is plugged in – CHECK IT OUT.
  • If the motherboard has cache on board, turn off External (L2) cache in the BIOS. You may have defective L2 cache, which means the board will need to be replaced (or the COAST module, whichever applies)
  • Set your BIOS to factory defaults (there is usually a couple of menu choices for BIOS defaults and SETUP defaults). It is possible you have a conflict in your BIOS settings.
  • Eliminate all unnecessary devices and device drivers, then boot again. You may have an IRQ or DMA conflict, or some drivers may be conflicting with each other. You can eliminate ‘boot up’ device drivers by placing an REM statement in front of the driver in the CONFIG.SYS file, which makes it a remark statement. If this turns out to be the problem, re-introduce devices or drivers one at a time until you determine which one is causing the lockup.

1.3 Operating System not Found or Boot Device Missing

  • Make sure your IDE cable is plugged in properly. The colored edge of the ribbon cable should be plugged into pin 1 of both the motherboard connector and the hard drive.
  • Make sure both ends of the ribbon cable are seated firmly. A loose cable may allow the drive to be detected, but unreadable.
  • Be sure you have the 5V power connector plugged into the drive securely.
  • Check that the BIOS settings are correct for the hard drive. If the BIOS does not have an auto-detect feature, you will need to find out the correct Cyl-Head-Sect information so the operating system can read the drive properly.
  • Check if you have a boot manager (such as On-Track) to support 540MB+ hard drives on a non-LBA system. This software is incompatible with hardware LBA and will render your device unreadable. In this case, you need to set the CMOS parameters for the hard drive to NORMAL (not LBA). If you want to use LBA mode, you will have to reformat the drive as follows:
    • Use the FDISK command with the /MBR option. This will remove the software from the master boot record.
    • Use FDISK to repartition your system
    • Use the FORMAT d: /S to format the drive and transfer the operating system
    • Re-install the complete operating system and applications, or restore from your latest backup.
  • Use the command FDISK /MBR (do NOT use this if you have disk manager software on your drive to emulate LBA mode on 540MB+ hard drives). This will re-create your master boot record without destroying any data on the drive (be absolutely sure to use the /MBR switch). When you issue this command, you will get no response back other than a blinking cursor and prompt.
  • Use FDISK to set the boot partition active.

1.4 Keyboard Isn’t Recognized

  • This is usually the result of the keylock pins being jumpered. On most motherboards there is a 5-pin connector labeled ‘Keylock’. Pins 1 and 3 are the Power LED, while pins 4 & 5 are the keylock. You may have accidentally jumpered the wrong pins and locked the keyboard out.

1.5 Slave IDE Drive Not Detected (Hard Drive or CDROM)

  • Be sure that the Primary IDE drive is jumpered for MASTER, and the Slave drive is jumpered for SLAVE. Some drives have the same setting for SINGLE and MASTER, but most have a separate setting. If the Primary drive is set to SINGLE, the Slave drive may not be detected.
  • Check the ribbon cable to ensure that the colored edge is plugged into pin 1 on the Slave drive.
  • Make sure the ribbon cable is seated properly at all connection points.
  • Be sure that the 5V power plug is connected securely.
2

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .