Static Electricity

[Fndr7070]

This may be off topic, but I didn't know where to post it.

My case has a door for the power buttons, CD drives, etc. This morning (while the computer was on), I went to close it. My finger touched the case (close to where the power button is), and I guess from walking around with socks on carpet, I had a good charge built up. I felt the shock, and then the computer turned off. I turned it back on, it posted, and said 'New CPU detected'. I just hit accept defaults, and it booted up and everything's fine.

I guess I'm just curious at to WTF happened???

 

[unreal111]

i am guessin here, maybe it got reset or something...

it happened to me too few years ago...

 

[chuckshissle]

That's just weird :? Either it's suppose to fry your system or not, but causing it to shut down and detect new cpu? You better try everything like all the task and test everyhardware in that computer to make sure that nothing is damage. :?

 

[Darkchyld]

Its possibile that the zap reset the BIOS. You might consider replacing the CMOS battery. I have some "must reading" on the effects of static charge on electronics. Let me know and I'll email it to you.
DC

 

[samir_nayanajaad]

This is what I think might have happened. Its just a theory because I don’t know how this works but from what little I do understand it sounds plausible.

The power switch just closes a circuit and allows the mobo to short this one wire on the power supply 20 pin connector that turns on the power supply and in turn turns on the pc (I think this because I know there is this one wire on the 20 pin connector that if you short it, it turns on the psu.). if that static shock went through the power switch and to that one wire on the psu its just like hitting the power switch again which turns off the pc. As for why it detected a new cpu I have not a clue.

If anybody can confirm or deny this little idea of mine I'd like to know just out of curiosity. Or maybe I should just look up how a pc boots from start to finish.

 

[bweir]

A static shock can be in the tens of thousands of volts, so it can damage ANY component that has a circuit. However, PC cases should be grounded, and touching it should NORMALLY discharge the shock right into the ground. However, since it did affect your system, i would keep a wary eye out for any strange errors or component failures at any point in the future. It will most likely survive relatively unharmed, but that jolt can weaken a component instead of disabling it outright, leading to problems in the future. It's like a power surge that gets past your surge detector, not good under any circumstances.

My suggestion, just to be sure: Run a long burn-in test of the CPU, Memory, and video subsystems for 12-24 hours, if it holds up without an error, you should be fine. If not, well, just hope for the best.

 

[Pain]

I've seen similar things, like putting the side case back on a machine and having it reset the box due to static. I don't find it very odd, and I've also seen where machines shut down improperly will ask you to check the CPU settings. Just check the bios to be sure everything is still set correctly and don't worry about it.

There could be damage from it, but if there is what are you going to do about it other than replace the bad part?

 

[chuckshissle]

Its possibile that the zap reset the BIOS. You might consider replacing the CMOS battery. I have some "must reading" on the effects of static charge on electronics. Let me know and I'll email it to you.
DC

But the mobo and other components in the case is not suppose to make contacts (electrical) with the case, unless his computer does.

 

[sturm]

Stranger is right. all components are grounded to the case. pci cards have the metal plate thats tied into the card which touches the case. Cdroms have a metal housing thats in contact with the case. The motherboard is grounded at each screw and at the backplate connections - mouse, usb, and other ports.
Its not an electrical ground but an earth ground.

30 volts is enough to fry electronics. most door knob type zaps are upwards of 2000 volts plus. The really good zaps are above 10,000 volts.

Remember its the amps that kills you not the volts.

 

[Anoobis]

30 volts is enough to fry electronics. most door knob type zaps are upwards of 2000 volts plus. The really good zaps are above 10,000 volts.

Remember its the amps that kills you not the volts.

Yes, R.I.P. ole Diamond Viper V330. Still brings a tear to me eye!

 

[mpjesse]

Actually... the typical "door knob zap" is over 20,000 volts. ;-)

-mpjesse

 

[chuckshissle]

Stranger is right. all components are grounded to the case. pci cards have the metal plate thats tied into the card which touches the case. Cdroms have a metal housing thats in contact with the case. The motherboard is grounded at each screw and at the backplate connections - mouse, usb, and other ports.
Its not an electrical ground but an earth ground.

30 volts is enough to fry electronics. most door knob type zaps are upwards of 2000 volts plus. The really good zaps are above 10,000 volts.

Remember its the amps that kills you not the volts.

The cards has metal for securing but still it doesn't provide a direct electrical bridge to the graphics card. Yeah, try removing it to find out for yourself.

And what of with acrylic cases? and test system that is just lying on the table?

The ground is taken care of the psu. Hence the three plug, negative, positive and ground that goes through the power outlet then go to the ground(earth).

 

[samir_nayanajaad]

The ground is taken care of the psu. Hence the three plug, negative, positive and ground that goes through the power outlet then go to the ground(earth).

Uh just so somebody doesn’t get confused by this, the reason for 3 prongs is a power a ground and a safety ground in-case the normal ground goes bad, and not all houses have this feature in the wiring (just old old houses). The way that is written it sounds like the negative and the ground are 2 different things when they are not, just 2 different paths to ground.

 

[Pain]

And what of with acrylic cases? and test system that is just lying on the table?

Both are poor practices, IMO.

 

[nigelf]

... and all houses here in the uk have three pronged plugs.

hate those .. so big.
always have to stick a pencil into the "ground" socket so i can connect my mobile phone charger, otherwise it blocks the 2 other sockets.

 

[Darkchyld]

Look very carefully, motherboards have an electrical contact at the mounting holes, these rest on the "posts". In the MB itself are various "traces" that are, for a better term, grounded there. Find an old MB and explore it with a meter, you'll find it intersting.
Also, a static charge or "zap" is not like the flow if current in a circut. Its more like an incredibilty short and intense pulse resulting in some very high EM fields, induction, and high local currents. Just how is the infomation stored in CMOS? In many tiny capacitors, holding "charge". It doesn't take much to "reset" them. (Thats why BIOS needs a battery to maintain the info).
I have a facinating industry paper on the subject. Wish I could post it here. Pm me or send me Email and I'll attach it in the reply. As for "grounds", careful, they are "earth ground", the third prong on a plug and circuit grounds, the return on say the 12Vdc line. They are seperate and different. Anyone worked on a TV without an isolation transformer? ( and still live to tell about it!).

DC

 

[Fndr7070]

Hm. Most of what you guys said flew straight over my head. But DC, I will PM you for that technical paper.

I checked the BIOS. everything seems fine. I didn't really change anything though. I'm more of a 'put it together and make it work' guy, as opposed to a 'put it together, make it work, then tweek the hell out of it' guy I wouldn't have a clue as to how to replace a CMOS battery.