bowen179

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Mar 27, 2012
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I have a i7 3770k ivy bridge installed in my newly built system. The problem im having is after installing everything into the case I booted up the computer and a got a screen telling me that the cpu fan was bad. Thinking it was a faulty intel fan I installed a zalman cnps9500 cpu fan. I made sure to put enough arctic silver onto the cpu and installed the fan. As soon as i turned on the computer i got an electric burning smell and a very very small amount of smoke near the cpu but everything seemed to be working fine except now nothing will display on the monitor. Is my cpu dead? it turns on normally all the fans work properly just no display or could it be the motherboard?(hopefully this)
 

diellur

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Apr 7, 2011
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What was the thermal paste you used? Some have metal content, and if you got even a small amount onto the motherboard you can short circuit the circuitry...I'm wondering if this is what you've done. Regardless, CPUs are robust and swapping out a cooler is not likely to damage it...your description of what happened and the problem you now have indicates a dead motherboard. If you have access to another S1155 motherboard, stick your Ivy CPU in that and see if you can get an image.
 

night wolf

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Jan 1, 2012
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just make sure before you open the case to put your finger on the case for at least 3 seconds before you touch any of the hardware!

Even the smallest of ESD can blow chips on your mobo and your cpu.
 

InvalidError

Titan
Moderator

Why three seconds? If your body is charged with any significant amount of electrostatic potential, it will instantaneously discharge as soon as the gap gets small enough for arc over. If the potential is too low to arc over, the amount of electrostatic energy should be well within semiconductors' human body and machine model discharge tolerances... and opening the case without touching it would be a difficult feat.

The biggest danger is charging back up after initial contact and forgetting to discharge again before touching something else.

In this case though, the OP said he used Arctic Silver and if he put so much of it that it overflowed onto the CPU substrate, it might have shorted out, nothing to do with ESD.
 

night wolf

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I never said he should open the case without touching it. i only gave him a fair warning on what to look out for, before he touches anything and damaging the hardware.

30v can destroy any chip on the board and cpu, no one can feel or see that amount of volts. it requires 8000v to see a discharge.
 

rdzona

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Oct 31, 2011
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Yeah ditto what invalid wrote. I also thought the same thing when I read " I made sure to put enough arctic silver onto the cpu". That sounds like he could've put to much on and then it oozed out the side without him knowing it b/c the HS was obstructing the view. I would pull that HS off and see what the result looks like, and yeah, all you can do after that is swap parts out to troubleshoot the suspect.
 

This is funny. InvalidError's right about this.

You really should take precautions and while static can harm components, I think Tom's did an article/experiment a few years back about purposely trying to ruin components with static and how extremely hard it is to ruin modern components with a static charge. But I digress...

As far as this OP's concerned, Smoke and electrical smells are bad by any means.

bowen179- Where did the smoke come from? The CPU socket?

If you use the right amount of AS5, you won't see smoke or smell anything. That is likely not the cause. If you use too much AS5 and get it on exposed metal on your board, your PC will short, but you won't see smoke or smell that electrical smell either.
 

InvalidError

Titan
Moderator

You won't be destroying many ICs with only 30V of HBM ESD, that's a tiny amount of energy and less than 30mA peak current. Under normal circumstances, most discharges would happen from IO pin to power/ground where clamping diodes, termination networks and capacitive loading often provide more than 1kV of HBM ESD protection. That's why most connectors, edge, socket and other interfaces are designed to maximize the chance that power/ground pins/pads will be the first to make and last to break contact - if any ESD occurs, it maximizes the chances that it will take the most rugged path.
 

InvalidError

Titan
Moderator

Most components are a lot more rugged than that and your linked video also states that modern devices are a lot more ESD-tolerant than older devices.

When you handle something like a CPU, you grab it either from sides/corners or pinch the heat-spreader and caps on the under-side. In either case, any ESD across the edge would jump to the substrate's internal ground/power planes with almost infinite ESD tolerance. No real ESD risk unless you touch IO pads which you should be avoiding anyhow since you do not want to get finger oils/moisture/contaminants onto LGA pads in the first place and the mere positioning from which you have to pick up a CPU (flat in a socket or packaging) also makes it difficult to grab it in an ESD-hazardous manner. (touch IO pads)

While taking ESD precautions is always a good thing, it usually takes extraordinary negligence to actually manage to zap a CPU with it.
 

InvalidError

Titan
Moderator

Make sure you check for any paste that might have overflowed from under the heatsink and touched traces/vias on the CPU's substrate. If you saw smoke, there should be signs of something burning up somewhere.