Getting small electrical shocks from the rig

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Hello,

I've experienced some electrical shocks from my gaming rig lately since I installed my new 1070 ti, I lost my 780 classified for no obvious reason and I don't want to lose my new 1070 ti.

Could there be something wrong with the rig? Or this is normal? Could there be something shorted inside the rig?
 

poisonite101

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Are you in a carpeted room? Perhaps there is poor grounding on the case combined with static electricity accumulated in your own body that's causing the shocks.
As a precaution, I would examine the system and ensure there are no stray screws or other conductive materials where they shouldn't be.
 

TJ Hooker

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Do you get shocks when you touch other metal objects in your house? If so, getting a little shock when you touch your PC may be normal. I live somewhere with low humidity and carpeted floors, I get shocked almost anytime I touch something grounded in winter (metal lamps, the screws on light switch panels, my PC, etc.). I've taken to just touching a metal lamp to ground myself before I touch my computer.
 

WWP

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No.

Perhaps there is poor grounding on the case combined with static electricity accumulated in your own body that's causing the shocks.

At first time I got the strike, I thought so that it could be a static charge. But I did some testing a moment ago, I used a DMM to measure any voltages and then I also use the current measurement, found like 4-6 mA between the ground of the GPU and the ground of the motherboard.

Also whenever I touch the back of the PSU I get a strike then I touched the back of the rig I get the same one by touching the corner of the rig. I don't know if that's normal.

As a precaution, I would examine the system and ensure there are no stray screws or other conductive materials where they shouldn't be.

I think it looks OK, there are cables for the top fans not connected yet because I'm using the front ones. Other things I think they are OK I don't know it's a strange thing because before I didn't experience such things by moving or touching the rig when it's on.

Other screws are on the bottom of the rig I don't think there's a problem with that.

It's my first time putting the rig on a solid floor, maybe it's normal grounding behavior. But I think there shouldn't charges leakage according to the setup.

Maybe I should take out the motherboard out of the rig and the PSU inside.



OK, I understand. No, currently I don't get shocks when I move in the house. It's like obvious problem with the case of the rig. Maybe something is leaking current, But I used the DMM to measure any voltages with the ground of the system.


 
If the shocks didn't happen before the graphics card installation, i'd be inclined to say that your computer is no longer grounded properly. Physically inspect the graphics card and where it's installed. There is metal touching metal somewhere.You could have installed the card in such a way where metal is touching metal somewhere, where it shouldn't be. If you absolutely cannot find the problem and reinstalling the old graphics card solves the issue, then the issue is with the new graphics card. RMA it because the card likely has a flaw and is not grounded.
 

TJ Hooker

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When you say the ground of the graphics card and mobo, what exactly are you referring to? How did you determine the points you're measuring are ground? Also, how did you measure current? You have to measure current is series, not in parallel, so I don't know how you could do that properly without some sort of riser.
 

WWP

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Well, I disconnected everything and started to connect things one by one. Eventually I found that the CPU power cable is one of the problems, if there are other things that may share some grounding problems.

I have to say that the 12V rail of the PSU failed before months, and it was the output power mosfets and I replaced them. But could be there any problems with my soldering operation? That one of the things I'm thinking about.

If not, then there's something wrong with the motherboard.

20181216-221726.jpg




1. I was testing if the ground of the mobo and the gpu are shared. And they are shared.
2. With the DMM on the continuity measurement.
3. With the ammeter, yes I know I have to measure in series, but I thought to test of I can do another path of the current with the ammeter to the ground or my hand, but didn't measure any currents.
 

WWP

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I disconnected everything and connected the power rails. I still get a strike from the motherboard ground!

It's either the motherboard or the PSU. But I think the PSU could be OK.

One thing I have to mention here, is that this PSU failed before months, and the problem was with the 12V power MOSFET. It wasn't working at all because the 12V rail is feeding the 5 and 3.3V rails. So I replaced the MOSFETs and it worked like a charm.

But there might be a possibility that there could be another problem or other broken components I wasn't aware of.

Or the motherboard, this motherboard actually took a hit during airflight shipping process, and the my first gpu gtx 770, wasn't screwed. So the gpu got off its slot and was rolling inside the rig all the time of that shipping, of course when I recieved it, the gpu was broken and there is a problem with the fans pins, one of the fans ports doesn't boot at the same time of the other port, it take a delay then the fan LEDs launches and the fan spins.

This is my current setup.

IMG-000000-000000.jpg


I need a PSU, to test this rig, but the problem is that in this city there are no famous places where I can test it! Maybe I can try and take the motherboard only to test its short, I think that would be the best solution to figure out which one is causing the problem.
 

WWP

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>>> a quick update, I just went to the setup to test something, everything is powered OFF, and the switch of the PSU is OFF too. I touched the motherboard and there was a strike! So I disconnected the power cable of the PSU and the charge just gone, THEN, when I tried to connect the power cable and my HAND was on the PSU case I got a strike!

I think it's the PSU.