[Solved] Dead MB?

Just want to run a quick check by the forum to make sure I'm not missing anything.

In one of my computers I have the following motherboard http://www.newegg.com/Product/Prod [...] 813128347.

The computer is not booting successfully. When I turn it on it loads the motherboard splash screen and then stays there for about ten seconds and then reboots. This process will repeat continuously as far as I can tell.

I can not get into bios (nor do any of the keyboard input options work).

I have trying resetting motherboard via the jumpers and have also removed reinserted the battery. I have tried different RAM chips in different slots. I have tried removing everything except the vid card, processor, fans, and RAM.

I do not receive any beeps from the MB.

Any other steps, am I missing another component, or do I rule this MB dead?

Thank you for your help.

I have disconnected the hard drive and do not have an onboard video option. The board has been functioning properly for about year (which I should have been clearer about) so I don't think there is physical problem with the board.

Thank you for the advice.

get the memory out and try booting if no bip: motherboard or processor problems

Well I tried it with a different power supply but the results were exactly the same. So unless both power supplies are duplicating the same problem it looks like it is the mothboard. If anyone has any other ideas to try I'd like to hear them but it looks like it is time to replace the MB.

Thanks to everyone for the help.

What follows is pretty much my "standard" troubleshooting reply.

Try to verify (as well as you can) that the PSU works. If you have a multimeter, you can do a rough checkout of a PSU using the "paper clip trick". You plug the bare PSU into the wall. Insert a paper clip into the green wire pin and one of the black wire pins beside it. That's how the case power switch works. It applies a ground to the green wire. Turn on the PSU and the fan should spin up. If it doesn't, the PSU is dead.

If you have a multimeter, you can check all the outputs. Yellow wires should be 12 volts, red 5 volts, orange 3.3 volts, blue wire -12 volts, purple wire is the 5 volt standby.

The gray wire is really important. It sends a control signal called something like "PowerOK" from the PSU to the motherboard. It should go from 0 volts to about 5 volts within a half second of pressing the case power switch. If you do not have this signal, your computer will not boot. The tolerances should be +/- 5%. If not, the PSU is bad.

Unfortunately (yes, there's a "gotcha" ), passing all the above does not mean that the PSU is good. It's not being tested under any kind of load. But if the fan doesn't turn on, the PSU is dead.

On to the real troubleshooting ...

Disconnect everything from the motherboard except the CPU and HSF, the two power cables going to the motherboard,and case power switch. Boot. You should hear a series of long single beeps indicating missing memory. Silence here indicates, in probable order, a bad PSU, motherboard, or CPU - or a bad installation where something is shorting and shutting down the PSU.

To eliminate the possiblility of a bad installation where something is shorting and shutting down the PSU, you will need to pull the motherboard out of the case and reassemble the components on an insulated surface. This is called "breadboarding" - from the 1920's homebrew radio days. I always breadboard a new or recycled build. It lets me test components before I go through the trouble of installing them in a case.

It will look something like this:
http://www.tomshardware.co.uk/foru [...] _13_0.html
You can turn on the PC by shorting the two pins that the case power switch goes on.

If you get the long beeps, add a stick of RAM. Boot. The beep pattern should change to one long and two or three short beeps. Silence indicates that the RAM is shorting out the PSU (very rare). Long single beeps indicates that the BIOS does not recognize the presence of the RAM.

If you get the one long and two or three short beeps, test the rest of the RAM. If good, install the video card and any needed power cables and plug in the monitor. If the video card is good, the system should successfully POST (one short beep, usually) and you will see the boot screen and messages.

Note - an inadequate PSU will cause a failure here or any step later.
Note - you do not need drives or a keyboard to successfully POST (generally a single short beep).

If you successfully POST, start plugging in the rest of the components, one at a time.

I want to thank everyone for their help, I got a lot more replies than expected. I replaced the MB today and everything is running again.