Troubleshooting system boot issues

Processor Issues
No boot situations can be caused by any of the following.

If you have installed an incompatible processor, the system will not boot. Ensure the selected processor model is correct for your desktop board. Some processors require specific desktop board versions and BIOS revisions. To find the supported processor list for your board, go to Supported Processors. If the processor is compatible, try removing and reinstalling the processor to ensure it is installed correctly.

If the processor overheats, the system may not boot or may shut down shortly after booting.

* Make sure the fans on the processor are connected properly and running.
* Make sure that the thermal interface material or the thermal grease is applied to the processor properly.
* Make sure that the power supply fan is running properly and any other external case fans are running properly.
* Make sure that the air intakes for the external fans are unobstructed and have at least several inches away from walls and other items.


Memory Issues
No boot situations can be caused by any of the following.

* If you have installed incompatible memory modules, the system may not boot. Verify the memory you've installed has been tested with your board. To find the tested memory list for your board, go to Tested Memory. If the memory is compatible, try removing and reinstalling the memory modules to ensure they are installed correctly.
* Some desktop boards require you to populate the memory sockets starting with the first socket. The product guide for your desktop board will indicate such a requirement.
* If you have defective memory modules, the system may not boot. One, two or three beeps at boot indicate defective memory. To isolate a specific memory module as defective, boot the system with just one memory module installed at a time.


Monitor Issues
No boot situations can be caused by monitor configurations. Check the following:

* Make sure the monitor is plugged in and turned on.
* Make sure the video cable is connected properly at the monitor and the computer.
* Check the brightness and contrast controls on the monitor. The monitor may be dimmed where you cannot see anything on the monitor.
* Most monitors have a light indicating its current status:
o A green light indicates the monitor has sufficient power and is getting a video signal.
o An amber light appears if the monitor has power but it is not getting a video signal from the computer. This indicates the problem is most likely in the computer.
o If the light does not turn on at all, it is likely a problem with the monitor itself. Make sure that the monitor is connected to a working AC outlet. If there is an on/off switch for the outlet, make sure the switch is on. If the problem still persists, try replacing the monitor or try the monitor on different AC outlet or a different system.


Power Supply and Chassis Issues
No boot situations can be caused by any of the following power supply, chassis or fan issues:

* Verify that your chassis and power supply is appropriate for the processor model and frequency and the desktop board you have.
o An ATX12V or SFX12V with the 2x2 connector is required for all Pentium® 4 processor based and higher Intel® Desktop Boards. Power consumption requirements for high-end video cards, sound cards, peripherals, and the Pentium 4 processor will exceed the typical 5A current capacity of standard ATX & SPX power supplies.
* Do not use 2x2 power cable adapters with non-compatible older power supplies.
* Verify that the power supply has the capacity to power all the devices used in your system.
* Ensure the power cord is firmly connected to the power supply and the AC outlet.
* If the power supply or the AC outlet has an on/off switch, make sure that it is on.
* Determine power supply voltage selector setting (230 volts vs. 115 volts) is correct.
* Check for foreign objects inside the chassis such as screws that may ground the desktop.
* Attach the desktop board correctly to the chassis base with the spacers/stand- offs. Make sure not to tighten the screws too much.
* If possible, use a voltmeter to verify that each output from the power supply is correct. If any output is very low (especially the +5 volt output), consider replacing the power supply.
* If possible, use a voltmeter to verify the PowerGood signal is +5 volts. If the signal is below 1.0 volts, there may be a short or overload causing a constant reset. Consider replacing the power supply.


Cable Issues
No boot situations can be caused by any of the following cabling issues:

* Make sure the drive ribbon cables inside the computer are attached correctly and securely. For IDE drives, check the orientation of pin 1 of the hard drive cable. A cable connected backwards may cause the computer not to power up.
* Check that the cables connecting the chassis front panel to the desktop board are plugged in properly to the onboard headers.


Electrical Short or Overload
An electrical short or overload may cause a system not to boot.

Check for shorts and overloads by removing non-essential items such as extra controller cards or IDE/ATAPI devices. Keep only the desktop board, power supply, memory and processor installed. If the system boots, it is possible there is a short or overload with one of the components that you removed or one of those components is faulty. Replace each of non-essential items one at a time until you isolate which one is causing the problem.

If the problem occurs even after removing the non-essential components, the problem has to be with the desktop board, power supply, memory or processor.


Defective Components
Defective components, especially processor and memory, can cause a system not to boot up properly.

* Swap the memory modules with known good memory. In addition, test the suspected memory in another known working system.
* Swap the processor with a known good processor. In addition, test the suspected processor in another known working system.




System Used to Boot up and Now Does Not
Changes to your computer's configuration can cause your system to not boot properly.


New Processor or Additional Memory was Installed
If you upgraded the processor or added memory:

* Some processors require specific desktop board versions or specific BIOS revisions.
* Make sure the new processor is supported for your desktop board. To find the supported processor list for your board, go to Supported Processors.
* Make sure the new memory modules are supported for your desktop board. To find the tested memory list for your board, go to Tested Memory.


New PCI or PCI Express* Card was Installed
If you installed a new add-in card to a PCI or PCI Express slot and now the system won't boot:

* Some PCI Express graphics cards require additional power.
* Remove and reinstall the new card to make sure it is fully seated in the slot.
* Try the card in a different slot, if possible.
* Make sure other devices and cables inside the chassis were not disturbed or loosened when you installed the new card.


New Drive was Installed
If you added a new drive (hard drive, CD-ROM, DVD) and now the system won't boot:

* Make sure all drive cables are properly connected.
* Make sure the correct power cable is connected to the new drive.
* Make sure any drive jumpers (master, slave) are configured correctly according to the manufacturer's documentation.
* Make sure other devices and cables inside the chassis were not disturbed or loosened when you added the new drive.


New Software or Drivers were Installed
If you recently installed new software or new device drivers:

* Try booting into Safe Mode and uninstall the new software or driver. If you can now boot normally, there may be a compatibility issue between the new software or driver and some component in your system. Contact the software manufacturer for assistance.


Settings Were Changed in BIOS
Certain changes in BIOS settings (such as chipset timing or latency, memory timing or latency, processor clock frequency, etc.) can cause a system to no longer boot.

If you are able to enter the BIOS Setup by pressing F2, reset the BIOS to factory defaults by pressing F9. Save and exit the BIOS Setup.

If you cannot enter the BIOS Setup, clear the CMOS:

1. Turn off all peripheral devices connected to the computer.
2. Disconnect the computer’s power cord from the AC power source (wall outlet or power adapter).
3. Remove the computer cover.
4. Locate the battery on the board (see figure below).
5. With a medium flat-bladed screwdriver, gently pry the battery free from its connector. Note the orientation of the “+” and “-” on the battery.
6. Wait one hour then replace the battery.
7. Replace the computer cover.
8. Plug the computer and all devices back in.

You may also need to perform a BIOS Recovery after clearing the CMOS.


Other Boot Issues

Resolving Slow Boot Times
Check the following tips to speed up the boot time of your computer.

* Set the hard drive as the first boot device in the boot order in the BIOS setup (Boot > Boot Device Priority menu).
* Enable Intel® Rapid BIOS boot in the BIOS setup (Boot menu).
* Disable Hard Disk Pre-Delay in the BIOS Setup (Advanced > Drive Configuration menu).
* Disable system functions and features if you do not need them. Examples include:
o Legacy USB - this must be enabled if you use a USB keyboard or USB mouse outside the Windows* environment (Advanced > USB Configuration).
o Unused I/O ports, such as serial, parallel and IEEE-1394 ports (Advanced > Peripheral Configuration menu).
o Event logging (Advanced > Event Log Configuration menu).

To enter BIOS Setup, press the key after the Power-On Self-Test (POST) memory test begins and before the operating system boot begins.