SOLVED Static Shock in PC Case and Monitor Going Black

[yusufjee]

I have ran into a fairly complex problem which i have never encountered before in all my years building custom machines

A few weeks back i rearranged the USB peripheral positions on my Desktop, nothing out of the ordinary just swapped places of a few peripherals and that's literally all i did. Keep in mind while doing this my PSU power was off, i do that always. Now i plug the PSU power back in and start my PC, to my surprise i felt major static on the side door. I went around touching the casing and felt static on both sides and front panel. When i touched the screws on the back of casing i felt minor electric shock, and same for USB port/audio port on front panel. Now this was the first syndrome, i didnt give it any attention i thought it is temporary and will go away.

But right after this i noticed my monitor is not on although i could see the orange light which tells that the monitor is plugged in waiting to get the video signal. I did the restart 2 or 3 times from PC reset button and finally got the monitor to show the bios start up screen and at this point the monitor power light turned blue which indicates it is getting signal. The windows 7 startup screen loaded fine but before loading the windows login screen there is always that 2 second gap where screen goes black and comes back on login screen. Well that didnt happen for me, the screen went black and stayed black and all i could hear the windows login screen load from the sound but there was nothing on screen. I input my login password on black screen and hit enter and then i could hear from the sound that the windows is loaded but screen was still black.

After much deliberation and research i unplugged the monitor and plugged it back in and voila the screen was back on. NOTE that i tried to use the power button on monitor but it didnt do anything. Well this is the temporary solution i am using for weeks now. Basically everytime i switch on the PC i have to make sure monitor is unplugged and first i start PC and then plug in the monitor. The monitor also goes black when i start a game because there is a certain delay when starting a computer game (COD:black ops 2/fifa 13 etc...) so basically i will double click the icon of the game and unplug the monitor and when i am sure the game is on from guess or sound, i will plug the monitor back in. How bloody stupid and annoying.

Keep in mind nothing was the matter with my PC before this, all was working fine. So far i have tried changing the power cables on both the PC and the monitor with 0 success. I havent tried changing the PC to Monitor cable yet but i did connect the cable on second connector on the back of graphic card. Today i also cleaned my PC from inside, unplugging everything from the back and basically cleaning with blower in my balcony. Also took out the graphics card and re-inserted it but there is no change, the symptoms persist.

My PSU: CoolerMaster GX-750 (http://www.coolermaster.com/product.php?product_id=6643)
Casing: CoolerMaster Gladiator 600 (http://www.coolermaster.com/product.php?product_id=6564)
Intel Motherboard
Sapphire Radeon HD 4870 Toxic series graphics card

I hope someone can help me. Much appreciate.

 

[ozan]

Try removing the usb headers from the Mainboard. Look for any cables or open ends in contact with metal interior. I had an akasa fan controller smoke from metal contact, I say you are on thin ice here Insulate metal contact. Since you moved around with the usb headers, one might have gotten in contact with somewhere it shouldnt be.

Alternatively try moving the graphics card to a different pci-e slot.

Hope you figure it out soon

 

[theELVISCERATOR]

I would test my wall outlet for voltage and proper ground also. Esp if you live in an area where power is dicey.

 

[Bobnova]

Definitely time to test the wall outlet ground. If you don't know how, hire someone to do it. No sense killing yourself!
You can get testers that you just plug in for $5 or so here.

Getting shocks from multiple parts of the case is frightening, as that implies something is generating a fair bit.

Were they "SNAP!" type static shocks, or more of a slow burn type shock?

 

[yusufjee]

Thanks all for trying to help. didnt get any responses on TomsHardware so this is a good start. I will test few things today as recommended by you guys after work.

Were they "SNAP!" type static shocks, or more of a slow burn type shock?

The ones on the side panel are slow burn i guess because i just feel the static when i rub my hand on it nothing major but when i touched the backscrew bare hands that was heavy, i felt a pinch. But i am guessing this is a major issue since my monitor is also suffering.

 

[larrymoencurly]

Some surge protectors and backup supplies have a light to indicate if the AC wall outlet is grounded or not.

Static shock feels very different from AC shock, which gives a buzzy feeling. I don't remember what DC shock feels like, but it's definitely different from static shock. The best way to test is with a voltage meter connected between the case and earth ground, and measure with with both AC and DC voltage settings. If the computer is actually grounded, the voltage will be zero.

3-wire AC wall outlets may have just 2 wires connected to them because the ground wire was left out. That's illegal unless that outlet is protected by a ground fault circuit interrupter (GFCI) to prevent harmful shocks, but even when a GFCI is used, it can still allow an annoying 60 volts AC to be applied to the computer case, through a pair of small capacitors that filter out line noise and RF emissions. The capacitance is low, to limit the current to safe levels, but the voltage can still damage equipment that isn't tied to earth ground, such as some monitors and printers (I hope you're plugging and unplugging the monitor's AC cord, not its video cable, which can let that 60V damage the monitor).

Sometimes power supplies are made wrong, even good ones. I had an Ultra by Wintech that didn't have enough insulation between the high voltage and low voltage sides, but a later version fixed that, by moving one small capacitor 1/4". With the PSU unplugged from the AC cord, turn on any rear power switch and measure the resistance between the case and each of the PSU's AC prongs. It should probably be at least 200,000 - 500,000 ohms (from the bleeder resistor).

 

[Bobnova]

I would stay the hell away from that computer (when plugged in, anyway) until you can check the grounding of that outlet (and power cord). It sounds very much like something inside the PC, likely the PSU, is leaking.

 

[puckr]

Dosn't sound safe for sure i would get some professional to maybe take a look at what it would be. Like everybody else here they said to stay away or be aware of it doing something weird! Sounds like the PC is shot though:/ Which i know sucks!

 

[irrykuxeh]

Yeah, I wouldn't be hanging around that computer if I were you. If you have a spare PSU, you might try that in your rig.

 

[yusufjee]

Alright guys i have sort of good news.

I ended up bringing my monitor to the technician and there was an issue with monitor power supply which is now fixed and monitor starts up fine now.

I couldnt diagnose the PC problem so i took the PC to the technician as well and he didnt find anything wrong with PSU or any other component. In the end i took it apart and rebuild the PC, now the static is not as bad as it was before but still minor persist.

Thanks all for your kind help.