Changed the case and .....

[bms1097]

Well as a birthday present for my brother I bought him a new case and DVD RW. We pulled the MB from the old case and put it in the new one, connected all the plugs and tried to turn it on and all that happens is as soon as I plug the plug into the power supply the light for the fans comes on real fast then off, fans turn a little and then I try to power on and nothing. Its an old Sony PCV-J150 I believe is the model (800 mhz Duron, 80G hard drive) Everything worked fine this morning before the switch. The new case came with a 400w power supply, would that be a problem for the MB? Thanks for any help and sorry for the long post

[rs8389]

400W should be fine for most computers, even new ones....  It might be that your PSU is simply dead.  Did you try putting your old PSU in the new case and running it?  If it works, then you've found your problem.  If not...  Are you sure you cabled everything correctly?  Did you make sure the cable that comes out of the power button on your case is connected to the corresponding pins on your MB?  Did you plug the main power cord from the PSU into your MB (I sure hope you did   Pretty simple, lol)?  Make sure of these and tell us if anything works.

[bms1097]

   yeah I made sure that the main power was in and the pins for the power button im pretty sure there good to, I used the the old plug for reference. I even tried the the old power supply and old switch and nothing

[rs8389]

Hmm...  Did you change anything else when switching the case?  New hardware?  Moved to a new room?  Anything?

Does anything happen when you press the power button?  Any sounds?  Any lights (Keyboard, mouse, power lamp, etc)?  Did you make sure you turned the PSU on ?

If none of those work, I'm stumped   Wait for help from the more informative members here

[Dell4700]

bms1097,

in addition to the previous advice-

- make sure the power supply is set at the proper input voltage (110/220) if it is switchable (unplug power before you make changes)

- make sure power to the motherboard is correctly placed and securely plugged (unplug power before you put your fingers in the case)

- and, of course, follow proper electrical safety procedures for anything you do with the system

Dell

[bms1097]

Well when I changed the case it came with a power supply, all the power plugs are plugged in all the way. I have tried both settings on the power supply and both have the same reaction, plug the power cord in and the fan spins a little and the led comes on for a second and thats it, nothing else. It doesn't beep or even spin the fans on the hard drive cooler. I have tried a different power supply and the same thing. I think the MB maybe shot because when we took it out of the old case we did it on the floor of the apt. Is there any way to test the MB, aside from what I have been doing? Thanks for the help and advice everyone.

[Dell4700]

bms1079,

Any of three simple possibilities come to mind - assuming the voltage to the power suppy is correct

(1)  if the new case comes with a power switch (not the button, but the switch behind it), then it may be bad or miswired - you stated that neither the old nor new PS worked in the new case - you can check this by putting the MB back in the old case and using the old switch/power supply - if it works in the old case, then it is probably the new switch - if it doesn't work as before, you may not be connecting the power correctly to the MB or switch.

A technician would simply check the switch circuit with a continuity/ohmeter (no power connected) and check to see output voltages from the PS are correct on the output pins (power on)

(2)  you may not be connecting the MB or switch power connector(s) correctly.  Google the MB Model Number and look at the service or installation manual to verify correct power connections.  Check the wiring diagram that came with the new case too.

(3) the PS may be bad, however you stated that neither the old or new PS worked.  It is not likely that both are bad.

As usual, use common electrical and ESD (electro-static discharge) precautions when working around any sensitive electronics.

If this doesn't help, give us some details about the MB, case and PS (model #s, manufacturers.

Note:  when you plug in power to the power suppy it is hot momentarily causing the fans and lights on some systems to briefly turn or flash.  This is normal for most.  The PS/MB then goes into a ready/standby state waiting for a signal from the switch to turn on.

Let us know what you find!

Dell

[It is usually the simplist solution that works]

[patio]

You might be experiencing a MBoard short on the case itself.
Get a desktop rubber mat for this test.
Remove the MBoard from the case and place it on the mat. Disconnect all devices leaving only RAM, CPU and vid card.
Hook up the PSU and see if will POST.
If it does add one component at a time until you find the culprit.
As always make sure you are properly grounded for this operation.
If it boots properly then you might want to get some new MBoard standoffs for re-assembly.

patio.  

[bms1097]

Well after thinking about what everyone mentioned I happened to notice one thing, my brother put the board in and I didnt tell him about the little spacers that go in between the case and the board. Then I pulled the board and tried it out of the case and it worked, put the spacers in and the board and everything is fine. Thanks again for the help everyone and like you said Dell, its usually the simplest solution. Thanks patio, reading about a MB short caught my attention and made me look at the board better, thank you everyone.

[patio]

You're more than Welcome and thanx for the update...

patio.