When a computer suddenly wont boot, the problem doesn't necessarily have to be very serious. Startup problems are often just caused by software issues, rather than hardware fails – so no need to worry.
These problems will typically occur out of nowhere, with little explanation as to what is wrong. But the problem will often be solved doing a simple troubleshooting process. In this article you will learn how to make your computer recover from a near-vegetative state.
General troubleshooting steps
These are some of the things you can start by doing, to try and make the computer start again. This assumes that there's no power at all, (no fans speeding up. etc.)
- Cut the power by taking out the power cable, and wait for awhile before reconnecting the computer to the power.
- While the power cable is disconnected, open the computer and find the small CMOS battery, take it out for awhile and place it back in. Then retry booting.
If you do have fans speeding up, chances are that the problem is with the bios. Try step two in the list. If you manage to get the computer to reach post screen, you will most likely have fixed the problem.
After resetting the bios by taking out the small battery, you will need to re-configure your system-clock, and you may also need to re-configure your boot-device priority.
Deeper troubleshooting steps
If the above didn't work, and you have no fans running in the computer, you might still be able to fix the problem. But the chance that something serious is wrong with a hardware part increases. But at this point it may be a problem with the power supply, so if possible, try testing it by dissconnecting everything except for the motherboard.
If you do have fans running, its may be a problem with your graphics card. Either try replacing it, or testing it in another computer.
If you manage to boot
You can run a stability test, depending on how well you know your computer. If for example it has shown signs of instability before, you might want to run some tests overnight, which will target parts such as processor and ram, to see if anything is wrong with those. Its important to note, that a simple miss-configuration of the RAM and CPU could easily cause problems, these are usually resolved when it has been configured differently though.
When overclockers are testing different settings, they are sometimes using a free program called Prime95, which will target the CPU specifically. For testing the momory there is memtest86+, links provided last in the article.