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Comment by illumin8 | Hacker News Reader

This is what 864GB of RAM looks like after you laid it all out on a table without using ESD (electro static discharge) protection. A few of these DIMMs are probably bad now, but you won't know which ones because you're going to stuff them all in a Linux box that you built yourself... this is such a bad idea for a production system.

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In my decades of building and taking apart computers, I have never had static discharge ruin a component. I can't remember the last time I was shocked by static discharge for that matter.

Who are these people who need to be grounded all the time else they build up to component destroying levels of static?

You don't need to feel the shock for it to be enough to destroy a component.

ICs are more robust when they're built into a circuit, but it's still a good idea to use sensible ESD protection when handing electronics, especially if you're paying lots on production systems.

How do you know you never had? Are you saying you've never had any component failure, or any inexplicable crashes or unreliability?

I generally do 24-72 hour burn-in tests on my computers every time I put them together and I only take them apart when they need upgrading or something breaks.

Maybe I'm just incredibly lucky. Then again, I've watched Dell and IBM service techs take apart laptops we had on-site support for without ESD protection, so maybe everyone else is simply paranoid.

> Then again, I've watched Dell and IBM service techs take apart laptops we had on-site support for without ESD protection, so maybe everyone else is simply paranoid.

This is the correct answer. Either that or every single Apple, Dell or UofT tech ever needs to be fired because I've had frequent repair experience with all of them and not once have they ever worn a wrist strap or mat. In fact, most techs mock the idea in my experience.

I would consider it if I was handling literally hundreds of modules like this, but for regular old desktop PC support it's complete overkill. The time it takes you setup an anti-static mat and wrist strap every time you need to swap something out costs you WAY more overall than the occasional lost module, which rarely if ever happens. If you're really so concerned, set aside $100 to cover any potential dead module. $20 says you'll never use it and you'll make more money because you saved time.

Every field engineer is trained on the proper use of a static mat and wrist strap. It takes only 30 seconds to put one on. Just because the field engineers are lazy and are ignoring their training doesn't make the risk of ESD any lower than it is. In cold winter climates with forced air heating and humidity less than 10%, how likely is it to cause an ESD?

Inexplicable component failures; random errors weeks or even months down the road. These are all caused by ESD. Just because you want to ignore the laws of physics doesn't mean they don't apply to you.

> Every field engineer is trained on the proper use of a static mat and wrist strap.

Right, and they still don't use it and mock it as they are being trained.

> It takes only 30 seconds to put one on.

To dig out the mat and wrist strap, fold it out, put the machine on the thing and clip it properly takes longer than 30 seconds, even if you have it around already. On top of that, you have to do it every time you want in and out of the case, on every call or event, every time. That adds up quickly.

> Just because the field engineers are lazy and are ignoring their training doesn't make the risk of ESD any lower than it is.

If ALL field techs without exception don't use it and mock it because in practice the risk is so ridiculously remote that it's not worth dealing with, then yes, it does make it lower than people like you make it out to be. I'm actually going to trust the guy who does it multiple times a day every day for years and years over the guy who insists the risk is greater than has ever been proven.

Either way, why should you care? I'm the one who will supposedly be paying for all these random dead components. I mean it hasn't happened once in years of being a field tech and never once using a strap and neither has it happened to anyone I know and the people I know are mostly techs and never use straps, but who knows what the future will bring?

> Inexplicable component failures; random errors weeks or even months down the road. These are all caused by ESD.

How convenient. We get to blame all potential future failures on ESD too. Nothing is a bad part or wear over time. It was all caused by you touching it without wearing the magic strap.

> Just because you want to ignore the laws of physics doesn't mean they don't apply to you.

Or Apple, Dell or UofT either. I'm just going to have to assume there is a magical anti-static field over Canada then.

I used to be a Sun field engineer. I had a foldable static mat with wrist straps in the pockets. It literally took me less than 30 seconds to unfold the mat, slide on the strap, and throw whatever system board I was repairing on the mat. The mat was padded as well, so I didn't have to worry about finding a safe surface to drop a 10 pound system board on.

The reason why the Dell techs are not using wrist straps is because they are lazy, and they know that even if ESD causes a component failure, some other poor tech will get the follow up service call and just come replace another part, or replace the same part again.

Have you ever wondered why a lot of replacement parts, after being installed without ESD protection, somehow are DOA (dead on arrival)? The factory that manufactures them surely tests them before shipping.

Are you seriously arguing that static charges of several thousand volts can't damage integrated circuits?

Handle enough DIMMs and the benefits of ESD protection start to become obvious. I've seen a very high correlation between DIMM errors and whether or not I was using a wrist strap while I was fiddling with the computer. You don't need a noticeable spark or shock to make the DIMMs unhappy.

The important thing is to not scuffle around a carpeted room with your wool socks on and then pick up the memory.

It depends on the humidity where you live, and what kind of clothes you wear, and if you're on a carpet or tile, or probably what you had for breakfast etc. I've had ESD fry a hard drive a RAM module, and maybe an SSD (or maybe it was bad firmware).

Ahhh. I've never lived very far from the ocean, so it's always pretty humid. Plus, I've always had wood or concrete floors which limits static build up and wood or metal tables.

I suppose if you're in Arizona, static build up is a much bigger problem.

I'm in Arizona right now. I cuss out the static electricity about every other day, so, yes, around here I'd use an ESD wrist strap or something if I were going to handle DIMMs.

Some places get very dry and staticky in the winter. Grounding yourself can be as easy as pressing a bare ankle against a metal table leg; better safe than sorry.

The static fears came from the early unbuffered CMOS chips, which were insanely sensitive to it. Yes, in theory you can still wreck a chip that way, but for the most part it isn't going to happen unless you're in an environment that's unusually prone to static buildup.

IC are like cats. They both have 9 lives and each time you handle it outside a protective environment it loses a life (the IC, not the cat :-) You may not see a failure right now but you will see it later when the life-counter reaches 0.

You are probably more right than you know... I've always suspected something like this; although mainly that's just from my personal experience when I haven't used ESD, sometimes I've given a board a bad shock and it still miraculously worked afterwards. I've even seen people plug in power supplies backwards, smoke a component on a board, and have the computer still miraculously boot afterwards. No idea if the computer was stable long term, but it's surprising sometimes how much damage these components can take. Then again, on the other hand, sometimes they stop working when they are in a clean room where everyone wears Intel bunny suits and is grounded 24/7.

The DC took the photo for us, I'd have to check with them what precautions they took but it looks like the build station if my memory serves. The RAM went in Dell boxes.

You're probably safe. Most data centres have controlled humidity and anti-static flooring

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