Computer only works when case is open?

When the case is closed and I power up, the fans come on by the power supply and cpu BUT there is no beep, the hard drive doesn't come on, and the monitor says "no signal."

When the case is open the computer works as normal and is fully functional.

This is a computer that I built myself and has been working perfectly for about 6 months now until this morning when this started happening. Without going into detail about the specific components of the computer, what part or circumstance could be causing this?

All the wires seem to be where they should be, not tangled or caught on anything...

I'm so confused, like I said before if I leave the case open it works perfect???

Thanks for the help
10 answers Last reply
More about computer works case open
  1. this could be so many things but it could most likely be the power supply if theres no beep or no video input it could be the power supply. but there have been times where nothing happens on my computer cause of cpu temps are too high and it doesnt work. but even if the mobo doesnt beep then it most likely would be the motherboard. you got yourself a doosy, ask a friend to borrow some stuff and troubleshoot the parts all you can do for now wihtout buying anything new
  2. Can you elaborate on how the case gets closed?
  3. Is there a case open switch / alarm type config? You might want to disable it in the bios or just disconnect it. It could be confused and thinking the case is open when it is in fact closed and for "safety" reasons not allowing the machine to work properly? Just a shot in the dark here. Sounds possessed - or just getting old and stubborn.
  4. Thanks for your reply, the real doozy is that all the parts seem to be fully functional. The mobo will post and my power supply will power everything including the video card and the comp works fine, only with the case open... so wierd...
  5. System temps ok? Speedfan is a good program to take a look. Edit: My mistake; shortshift23 already mentioned temps.
  6. The screws are on the back and the whole side pops off. temps are good. no alarm set in bios
  7. andydolan, what case do you have? Check all connectors from the PSU. Something either has to move, gets shorted or open when you close the case.
  8. Let me ask this question another way:

    What needs to happen inside my computer for the initial "BEEP" to come from the mobo? I think if I knew the answer to this I could figure out what is broken?

    Thanks, I'm new at this :)
  9. It was an extra fan on the inside of the case on the side panel that opens. The plastic cylinder that holds it is pushing into the cpu power supply wire. If any pressure hits the wire the mobo wont post. I removed the fan and plastic cylinder and taped the wire to the case. Thanks ghislaing, I figured it out by turning it on and jiggling all the wires gently until one made it turn off.
  10. You should inspect that connector as it shouldn't fail when putting a bit of pressure on the cable.
Ask a new question

Read More

Motherboards Cases Computer