PC reboots if someone walk by

[churin]

It's worth a try, but no guarantees. I must admit that I am a little bit stumped by this as it is a most unusual problem.

I am well aware of that. I want to have the part around anyway.

 

[churin]

Hi, have you checked for stray strands or just one strand of wire sticking out where the reset switch is connected to mobo. It could be touching something?

It is one strand of wire about 12 inches in length with a reset switch fitted on one end. It could not stand itself so that it was touching something around.

Also check the main power supply cable from your wall socket, it could be a loose wire?
If connected to a filter after the main socket check for loose wires also.
If you haven't got a filter it could be transient/spikes in the voltage from the main power supply in your home.

There is a USP between the PC and the AC outlet. I have been using the same AC outlet, the same USP and the same AC cord to PC for the last ten years(the battery was replaced 3 times during that time). I built four different PCs so far and the first three did not have this problem.

 

[churin]

Dwarf has asked us for more help, so let me throw in my suggestions. First, try reading these links.
pc reboots if i touch the case - VideoHelp.com

http://www.daniweb.com/forums/thread15060.html

I have read the links.

Remove all hardware from the motherboard. DVD drives, video cards, hard drives, etc.

I have tried this but no avail. The video card could not be removed because the mobo does not have integrated video.

Actually, to make this as fail-proof as possible, remove the motherboard from the case as well.

I assembled the hardware system without using any case and installed the W7. After confirming everything was working fine, it was moved into the case.

 

[Darryl Licht]

Just another idea... have you reset the BIOS to factory defaults?

And everything worked fine outside of the case??? Strange indeed!

 

[churin]

The following is what I have determined :
1. Discharge of static electricity is cause of the problem not loose wire or intermittent connection, etc.
2. Discharge of static electricity into the reset cable only causes the rebooting problem. There are many cables and wire strands including the reset wire that are bundled together and neatly routed in the case(done by case vendor) but as long as the reset wire is unplugged from the mobo, the resetting does not happen.
If a separate strand for the reset wires as shown below is used, then discharging static electricity into the top plastic piece of the case does not cause resetting, but if the discharging is done into somewhere in the twisted strand, then resetting happens.
The problem seems to be that the reset wire's switch side end is held by a plastic piece. If this is made of metallic material and is integral part of the steel case, the problem would not happen.

 

[Darryl Licht]

Have you tried the on off switch in place of the reset switch... they are the same except a reset is a momentary switch... while on off is a regular switch. This might help show if it is just a bad/shorted reset sw... You can turn on system by using a spare jumper and shorting the on/off switch pin header on mobo.

 

[churin]

Have you tried the on off switch in place of the reset switch... they are the same except a reset is a momentary switch... while on off is a regular switch. This might help show if it is just a bad/shorted reset sw... You can turn on system by using a spare jumper and shorting the on/off switch pin header on mobo.

The switch as shown in the picture on my previous post is a spare switch not the one which came with the case. It did not have any effect on the problem.

 

[Darryl Licht]

Dang this ones a beeeyatch!

If I had the same issue... works fine outside case... doesnt work in case... I'd have to try a different case.

OR...you have one of those new coolermasters I see from the photos... painted or powdercoated in and out.... hmmm I wonder if it is a ground issue due to that paint???

Is there a chassis ground wire? If so, use a star washer under to bite into the coating and get a good ground... http://product-image.tradeindia.com/00119865/b/0/Star-Washer.jpg

 

[churin]

If I had the same issue... works fine outside case... doesnt work in case... I'd have to try a different case.

As I already stated in my earlier post, that will most probably solve the problem. But I would rather remove the reset switch instead.

OR...you have one of those new coolermasters I see from the photos... painted or powdercoated in and out.... hmmm I wonder if it is a ground issue due to that paint???

Yes, it IS a ground issue, but not due to the paint but due to the plastic part used for the case as stated in my previous post.
The case is CM STORM(SGC-2000-KKN1-GP) and the part assembly on the top side of the case is made of plastic material which holds switches(pwr,reset), LEDs, connectors(eSata, usbs) on ends of the cables and the wire strands running from the mobo.

 

[Darryl Licht]

Pehaps use a little sandpaper around the holes for mobo standoffs?

 

[Lava King]

If I may jump in here...

I've read this entire thread and I agree that it seems to be a grounding problem, or more specifically, an electrical noise problem.

I see that you have made sure that the motherboard is truly grounded to the case, but have you made sure that the case is grounded when it is plugged in?

To test this, first REMOVE the AC cord from the PSU. Now, set your DVM to Ohms at the lowest setting (probably 200 or 20) or continuity if it has that option. Touch the probes together to make sure it's working, you should see a very low reading (ideally 0 but more likely something less than 1 Ohm). Now touch one probe to the bare metal of the case and the other probe to the "prong" in the CENTER of the AC connector on the PSU. A reading of 1 Ohm or less indicates that the ground connection is good. Additionally, you can check your AC cord (disconnected from the wall socket and the PSU) for continuity while you're at it.

If the case is grounded correctly to the PSU, there is one more thing I can think of to check. Get an outlet tester (about 5 or 6 dollars) from your local discount store or hardware store. In case you haven't seen one, it looks like an AC plug without a cord. There are 3 neon lights in it that can reveal any wiring problems depending on which ones illuminate and which ones don't. If there's a wiring problem, then it's time to call a professional electrician.

If, however, all the wiring is correct, I don't know what the next step would be. Call an exorcist, perhaps.

An important safety reminder: NEVER attempt to use an ohmmeter or DVM set to Ohms on a powered circuit!

Keep us informed, I'm sure that everyone reading and responding to this thread is curious as to what the real problem is.

Kent

 

[Dwarf]

Have you tried the on off switch in place of the reset switch... they are the same except a reset is a momentary switch... while on off is a regular switch. This might help show if it is just a bad/shorted reset sw... You can turn on system by using a spare jumper and shorting the on/off switch pin header on mobo.

I've already suggested swapping the switches over. Incidentally, they are both momentary push-to-make switches. The only difference is that the operating button of the power switch is usually bigger than that of the reset switch.

 

[stormy13]

Just wondering if you have tried contacting CM and seeing what they have to say,

Cooler Master Forum • Index page

Maybe even try their live chat,

http://www.coolermaster-usa.com/livechat/choosedepartment.php

 

[churin]

Lava King;
The resistance between gound pin of the AC connector and one of the nine screws to fasten the mobo to the stand-offs is measured to be less than 0.2 Ohms(Reading resolution of the meter is 0.2 Ohm). I tested the AC cord as suggested and found no problem.

I have the AC wiring tester and it indicates normal as shown below picture.

 

[churin]

Just wondering if you have tried contacting CM and seeing what they have to say,

Nobody was on-line so I left a message.

 

[Dwarf]

Ok, here's another suggestion. You will need some wire for this. Strip the insulator from the wire at one end. You need to strip sufficient so that you can wrap the bare wire around the switch and then twist it together to ensure that it is firm. Route this wire away from the main reset cable and connect the other end to a point that you know is connected to ground such as the case of your PSU (or indeed use one of its mounting screws).

 

[Darryl Licht]

I advocate you try sandpaper, star washers, or similar around ALL grounding points... mobo standoffs, psu, switch mounting screws, etc. I bet the paint or powdercoated interior is the issue somewhere, this isnt a very old case and may it be an issue.

Its worth a try... and you've gained skill no doubt at removing and replacing your mobo.

 

[churin]

Ok, here's another suggestion. You will need some wire for this. Strip the insulator from the wire at one end. You need to strip sufficient so that you can wrap the bare wire around the switch and then twist it together to ensure that it is firm. Route this wire away from the main reset cable and connect the other end to a point that you know is connected to ground such as the case of your PSU (or indeed use one of its mounting screws).

I am unable to visualize exactly what you suggest that I do but what has been done and was posted before is the following:
The wire strand for the reset switch was wrapped around by aluminum foil for about four inches from the mobo side and the foil was grounded via a copper wire to the nearest mounting screw(one of 9 screws for ATX).
You stated "wrap the bare wire around the switch" but the switch assembly itself is not accessible. My experiment so far done indicates that the rebooting(resetting) does not happen if the discharge current is bypassed the reset cable.

 

[churin]

I advocate you try sandpaper, star washers, or similar around ALL grounding points... mobo standoffs, psu, switch mounting screws, etc. I bet the paint or powdercoated interior is the issue somewhere, this isnt a very old case and may it be an issue.

I would think the reasoning behind this suggestion must be that the mobo may not be adequately grounded to the case. However, doesn't the the result of the test suggested by Lava King prove otherwise?

 

[Dwarf]

Is it possible to have a shot of the inside of the case showing where the switches are mounted with the switches in situ? I need to be able to see the back of the switches clearly.