Hi everybody and thanks for taking the time to look at my thread. I am no stranger to PC builds and thought a simple case switch would not out smart me...but i am afraid to admit it has!!and it goes something like this.. I recently built a PC and fired it up for the first time. After a few seconds it shut down. So i pulled of the power switch connection from the mobo and used a screw driver to short the pins on the mobo and the PC fired up lovely. So i thought to myself it must be a faulty case switch and went through the process of changing the case(to another just the same). upon firing up the newly built unit exactly the same thing happened(at this point I'm getting a bit fed up) so again i think faulty case switch. Upon the 3rd build(again with a case exactly the same) i am faced with the same problem. I think to myself that no way can it be 3 faulty case switches in a row so i turned the 2 pin case switch connector block the other way round and re attached it to the mobo and it works like it should. The machine runs OK. But i always thought that the case switch was just an on/off type thing and by pushing the switch you are just making a connection the same as a screwdriver would do??? But thinking about it the two case switch wires are..1 orange and 1 white. If it is not supposed to matter what way round they go why are they color coded. Any advise to put me out of my misery is very mush appreciated.
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pc on/off switch..very strange goings on???
- Thread starter ckes101
- Start date
To be honest it shouldn't make any odds, but the case that you have may just have a strange type of switch. I have never had this problem myself. Normally the motherboard manual may point out the + & - pins, but as you say, the switch is only there to make a join in the two pins (short)
Maybe the switch has a strange action that creates a second short, but only happens when the connector is a certain way. Sounds a bit crazy, but you never know.
The only pins that normally require the correct polarity are the ones for the LED's (Power, HDD)
As I said, it could just be a strange case switch.
Maybe the switch has a strange action that creates a second short, but only happens when the connector is a certain way. Sounds a bit crazy, but you never know.
The only pins that normally require the correct polarity are the ones for the LED's (Power, HDD)
As I said, it could just be a strange case switch.
This kind of acts like you have a normally closed switches rather than normally open. It would fire up when the switch transfers back to connected when you release, then shutdown 5 seconds later because it thinks the switch is being held down. But that theory leaks because swapping the pins shouldn't affect the problem.
Try it with the reset switch and see if it makes a difference.
To verify the possibility would require an ohmmeter.
Is there a possibility that there is an internal LED? That would throw a possible one direction partial short into the mix.
Ed Fair
Give the wrong symptoms, get the wrong solutions.
Try it with the reset switch and see if it makes a difference.
To verify the possibility would require an ohmmeter.
Is there a possibility that there is an internal LED? That would throw a possible one direction partial short into the mix.
Ed Fair
Give the wrong symptoms, get the wrong solutions.
- Thread starter
- #5
Hi all...yes its totally bizarre. As soon as the power lead goes in the PSU the PC fires up and shuts down a few seconds later just like the on/off switch is being held in. Swapping the pins around solves the problem. I have a spare on/off switch in my tool box and when this is plugged in it works 100% fine what ever way round the pins are connected. I think i will just have to accept that its just one of those bizarre PC moments and leave it at that!!!
LawnBoy
MIS
- Mar 12, 2003
- 2,881
I have seen some switches that are designed for digital circuits that have built-in capacitors (actually, tank circuits) to help debounce them. I've never seen one used for a case switch, but it can explain the behavior you're seeing.
"We must fall back upon the old axiom that when all other contingencies fail, whatever remains, however improbable, must be the truth." - Sherlock Holmes
"We must fall back upon the old axiom that when all other contingencies fail, whatever remains, however improbable, must be the truth." - Sherlock Holmes
franklin97355
Technical User
Or that there is a built in led that has to be in the proper orientation.
The answer is "42"
The answer is "42"
- Thread starter
- #11
Greetings again every body. The case is just a cheapo i have been using for some cheap builds a link is here(hope i am allowed to put links in although I'm not really sure i am if not i apologies in advance)
I am going to take the front completely off one unit this weekend just so i can see the on/off switch for myself...i will keep you posted on what i find.
I am going to take the front completely off one unit this weekend just so i can see the on/off switch for myself...i will keep you posted on what i find.
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