Computer fails to boot

Tonight one of our computers decided not to boot after being logged out. Had been functioning OK for about 5 months. Computer is "cheap" Ei-Systems computer that has Windows XP Home, 1GB mem, 60GB Harddrive. I added a wireless network card in 5 months ago.

Currently there is no boot screen (nothing on screen at all) and no beeps - it is not possible to get into the boot menu. However, the main power-on button does light up, the wireless network card lights flash, the hard disk light is lit for a short while and the 2 fans are working.

I have checked that the monitor is OK by testing it in another computer. Also tried a different monitor in the defective computer - no change in symptoms. I have also changed wireless USB keyboard/mouse with wired PS/2 equivalents - no change in symptoms.

Any suggestions? What other hardware checks can I perform?

 

In the past I had a CMOS failure that sounded much like this.
If you dont know already, you could try popping out the battery (size of a nickel) on your mobo. wait 30 seconds to a minute, then focus on the jumper(http://en.wikipedia.org/wiki/Jumper_(computing)) beside it. say 123 . if jumper is on 2 and 3, put it to 1 and 2 vise versa. hold for 10 seconds. then put it back where it was originally. then put battery back.
The worst this will do is reset your bios to defaults and your clock, the best...your pc will boot
hope this helps

 

Sounds like a classic case of a dead PSU. If the machine was cheap built with a lot of no name components theres a decent chance that the PSU is also a no namer.

My advise is, assuming you hadn't changed any settings before shutdown is.. test the PSU or if you have a spare hook it up. You may also want to ensure that all expansion cards and the RAM is properly seated. Although if anything wasn't properly seated, assuming the system speaker is properly connected the BIOS would beep to warn you. The BIOS would also let off a series of beeps to warn if the memory was bad, unseated, VGA was bad unseated, CPU.. etc

A dead PSU will often leave the system just like you described it. Fans running, power light on, NIC flashing away and nothing on screen. It's like the lights are on and no one's home

Good luck!:major

 

Thats good advice from Jazagod but if it doesn't get it going, it could be the video card. I've seen it before on E-Machines. If it's on board video you should be able to disable it simply by plugging in an ordinary PCI or AGP card depending on what slots are in your machine.

 

OK, it was the CPU.

Tried different memory and mobo but no joy. Now have a new CPU, slightly faster than old one.

The root cause is cost cutting by automating the computer manufacture and cutting corners in components where possible. Mass produced cheap computers nowadays are designed, built by computers and not hand built nor tested as they leave manufacture. The testing is done by the consumer :cry . The first things to fail seem to be electronics either immediately or after a few months like this. Then, if OK, the next things to fail are the fans and hard drive after about 18 months. Basically, cheap mass built computers nowadays are very unreliable.