I'm trying to understand why ESD ( if indeed that’s what it is) on the external portion of computer case fried my motherboard on two different occasions over a 4 month period.
In each event, I was reaching to push the eject button on my DVD drive. When I pushed the “Eject” button on the front of the DVD Optical Drive I felt what I perceived to be a static spark. The ESD caused the computer to power off and in each of the two occasions; the motherboard underwent a catastrophic failure.
Had I been inside the case when this occurred, well, this would be a no-brainer as they say.
The only time I've heard of ESD on the external portion of the case causing a catastrophic failure was when the computer was not properly grounded.
After each of the two ESD events, I checked to ensure that my 3-prong outlet was properly grounded. The computer is connected to a Belkin 1100VA UPS which connects to 3-prong receptacle. The earth ground was checked with an inexpensive outlet tester (the kind that shows “open Ground”/Open Neutral/Open Hot/Hot/Grd Reverse/Hot/Neu Reverse/Correct) and a digital multimeter. All indications were that a good ground existed.
After each event I’ve even had an electrician come to my house and check the wiring/receptacle for proper installation/ground.
The mobo was inspected and the stand-offs were all verified to be in correct (none where they did not belong). The mobo was not making improper contact with the case as best as I could tell.
The power supply (a new PC Power & Cooling 610) was tested and found to be in good working order (using the test procedures provided by the manufacturer)
The computer (3-prong cord) was plugged into a UPS (no indication of a Site Wiring Fault) and the UPS is plugged into a grounded 3-prong receptacle.
It's possible but it just does not seem credible that the spark would have to jump from your finger through the non-conductive plastic of the button and enter a live circuit without encountering any grounded part of the drive's chassis or computer case first.
For the DVD Drive, the electrical grounding is handled through the power cable grounds. By removing the Bezel on the front of the DVD Drive it looks like the switch is supported by a metal bracket that is soldered to the circuit board. On the front surface of the switch there is a small metal shield with an opening just large enough for the activator button to protrude through. On the chance that a static charge winds its way around the outer button through the bezel it will be picked up by this shield and routed to the DVD's circuit ground and then to the DVD case.
I did, after the second ESD event, find a bare exposed wire on the Ribbon cable (pin 39, LED indicator) that connects to the DVD and to the Mobo that was most likely touching the metal case of the DVD drive. I was thinking at first that this bare ribbon cable wire touching on the metal DVD case might be the culprit.
However, a couple of PE-EEs that have reviewed these two events don't think that the Ribbon Cable is a contributor to the ESD causing a catastrophic failure of the mobo (twice). They just don't feel that even a short in that ribbon cable could lead to ESD given the low voltages in those conductors.
I've replaced the power supply, DVD Drive (& the obviously bad ribbon cable), case fans and taped over all unused Molex connectors.
I've placed an electrically conductive mat in front of my desk and computer with grounding straps to the grounded receptacle and a second grounding cord that has a wrist strap that is on top of my desk that I can touch before touching my computer.
The conclusion by the professionals that have reviewed my situation is that they feel that this occurred because something is just not properly grounded. I believe them too, but I just can't find anything other than the bad ribbon cable that seems to be out of order. I would like to know the culprit if it’s knowable
I did read about another person who recently had the same problem when he touched the eject button on this DVD Drive which caused he computer to power off. However, he was able to reboot and all seems to be fine for now (he might have some unknown latent issues though). He could not find a grounding issue either.
I trust and believe the professionals that have provided their opinions on this issue. However, I just can’t seem to find convincing proof as to the cause. I’m most likely beating a dead horse in the ground (no pun intended ) but I have always been a big believer in Peer Reviews as a good method for reviewing problems/solutions.
Has anyone else seen/heard of this type event?
Could it have been the DVD Drive (It showed to be grounded when testing with multimeter?
Could it have been the ESD coupled with the Ribbon Cable hitting the metal DVD Drive? Can I rule out this cable as being related to the problem or not?
(see snippet below). The grey colored portion below the ribbon is the top of the DVD Drive. When I checked if the exposed wire could contact the metal DVD drive, I saw that because of other power cable near by, the ribbon cable was pushed up and folded up on top of the DVD Drive and the exposed wire easily made contact to the metal case of the DVD drive.
Could it be something in the construction of my case? (Tests don’t indicate grounding issues.
Could I have just plugged a cable in incorrectly on both occasions that fried the mobo?
**broken link removed**
I’m even going to replace my case just out of fear/ignorance
Something was not grounded, but what?
At this point it may be to all speculation, but II would appreciate any further comments/thoughts on this situation. I'm just not convinced I've found a solution to my problem.
p.s., I do admit to being very anal retentive
Thank you
In each event, I was reaching to push the eject button on my DVD drive. When I pushed the “Eject” button on the front of the DVD Optical Drive I felt what I perceived to be a static spark. The ESD caused the computer to power off and in each of the two occasions; the motherboard underwent a catastrophic failure.
Had I been inside the case when this occurred, well, this would be a no-brainer as they say.
The only time I've heard of ESD on the external portion of the case causing a catastrophic failure was when the computer was not properly grounded.
After each of the two ESD events, I checked to ensure that my 3-prong outlet was properly grounded. The computer is connected to a Belkin 1100VA UPS which connects to 3-prong receptacle. The earth ground was checked with an inexpensive outlet tester (the kind that shows “open Ground”/Open Neutral/Open Hot/Hot/Grd Reverse/Hot/Neu Reverse/Correct) and a digital multimeter. All indications were that a good ground existed.
After each event I’ve even had an electrician come to my house and check the wiring/receptacle for proper installation/ground.
The mobo was inspected and the stand-offs were all verified to be in correct (none where they did not belong). The mobo was not making improper contact with the case as best as I could tell.
The power supply (a new PC Power & Cooling 610) was tested and found to be in good working order (using the test procedures provided by the manufacturer)
The computer (3-prong cord) was plugged into a UPS (no indication of a Site Wiring Fault) and the UPS is plugged into a grounded 3-prong receptacle.
It's possible but it just does not seem credible that the spark would have to jump from your finger through the non-conductive plastic of the button and enter a live circuit without encountering any grounded part of the drive's chassis or computer case first.
For the DVD Drive, the electrical grounding is handled through the power cable grounds. By removing the Bezel on the front of the DVD Drive it looks like the switch is supported by a metal bracket that is soldered to the circuit board. On the front surface of the switch there is a small metal shield with an opening just large enough for the activator button to protrude through. On the chance that a static charge winds its way around the outer button through the bezel it will be picked up by this shield and routed to the DVD's circuit ground and then to the DVD case.
I did, after the second ESD event, find a bare exposed wire on the Ribbon cable (pin 39, LED indicator) that connects to the DVD and to the Mobo that was most likely touching the metal case of the DVD drive. I was thinking at first that this bare ribbon cable wire touching on the metal DVD case might be the culprit.
However, a couple of PE-EEs that have reviewed these two events don't think that the Ribbon Cable is a contributor to the ESD causing a catastrophic failure of the mobo (twice). They just don't feel that even a short in that ribbon cable could lead to ESD given the low voltages in those conductors.
I've replaced the power supply, DVD Drive (& the obviously bad ribbon cable), case fans and taped over all unused Molex connectors.
I've placed an electrically conductive mat in front of my desk and computer with grounding straps to the grounded receptacle and a second grounding cord that has a wrist strap that is on top of my desk that I can touch before touching my computer.
The conclusion by the professionals that have reviewed my situation is that they feel that this occurred because something is just not properly grounded. I believe them too, but I just can't find anything other than the bad ribbon cable that seems to be out of order. I would like to know the culprit if it’s knowable
I did read about another person who recently had the same problem when he touched the eject button on this DVD Drive which caused he computer to power off. However, he was able to reboot and all seems to be fine for now (he might have some unknown latent issues though). He could not find a grounding issue either.
I trust and believe the professionals that have provided their opinions on this issue. However, I just can’t seem to find convincing proof as to the cause. I’m most likely beating a dead horse in the ground (no pun intended ) but I have always been a big believer in Peer Reviews as a good method for reviewing problems/solutions.
Has anyone else seen/heard of this type event?
Could it have been the DVD Drive (It showed to be grounded when testing with multimeter?
Could it have been the ESD coupled with the Ribbon Cable hitting the metal DVD Drive? Can I rule out this cable as being related to the problem or not?
(see snippet below). The grey colored portion below the ribbon is the top of the DVD Drive. When I checked if the exposed wire could contact the metal DVD drive, I saw that because of other power cable near by, the ribbon cable was pushed up and folded up on top of the DVD Drive and the exposed wire easily made contact to the metal case of the DVD drive.
Could it be something in the construction of my case? (Tests don’t indicate grounding issues.
Could I have just plugged a cable in incorrectly on both occasions that fried the mobo?
**broken link removed**
I’m even going to replace my case just out of fear/ignorance
Something was not grounded, but what?
At this point it may be to all speculation, but II would appreciate any further comments/thoughts on this situation. I'm just not convinced I've found a solution to my problem.
p.s., I do admit to being very anal retentive
Thank you