Am I am an idiot for not using a surge protected powerboard?

Does this mean my computer gets fried in a power outage? Which particular parts of the computer are most vulnerable to damage if I get a 'surge'?

  • 4
    Surge Protection isn't needed until it's needed. :) – Molly7244 Feb 24 '10 at 22:17

A HowStuffWorks reference on When to Use a Surge Protector,
this is a page from a list of pages on surge protection (move to the next page too).

This is my take on a surge impact to a home PC.

  1. If you are lucky, only the PSU will be damaged
    • after that, your motherboard regulators and graphics card can be killed
    • beyond that your processor and other motherboard components may be damaged
      you can also lose your monitor power circuits on the way
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  • My parents were using a cheap power strip that was supposed to have surge protection. Surge fried the whole power supply, but it was a cheap Dell PSU. Replaced it and billed the surge protector company for the cost of the new PSU + labor. That computer's still running Windows XP and I used it just last night lol. – NobleUplift May 6 '16 at 16:22

Is surge protection actually needed?

Depends on your definition of "need". If you decide that your computer isn't worth $20 (a year) of protection then no, you don't "need" one.

Am I am an idiot for not using a surge protected powerboard?

Not at all - you're just playing the odds. You are, in effect, saying "I bet my $1,000 computer that no damaging power surges will occur by the time I upgrade to a new system. If I win, I save $20. If I lose, I pay anywhere from $0 to $1,000 depending on the severity of any given surge."

With today's power systems in developed countries, it's actually a pretty reasonable bet - so much so that many companies have determined it's cheaper not to have surge protection and suffer the occasional consequence than it is to pay for the surge protectors. However, they have insurance for this anyway, that they are going to pay for whether they have surge protectors or not, so the financial dynamics make the bet pay off differently for them than you.

Does this mean my computer gets fried in a power outage?

Yes, and the damage is cumulative. Unless you have pure, ultra filtered AC power then your PC is constantly besieged by power spikes. The vast majority of them have no effect - they are under a thousand volts and last such a short time that there's no real measurable effect.

Those that are above 1,000 volts, or those that last for a long time (mS rather than uS) cause a minute amount of damage to the power supply of the PC. Typically they do not get through the power supply to other parts of the computer, but I wouldn't guarantee that with cheap power supplies.

Once you've received enough of these more significant spikes, another one comes along and follows the carbon track laid out by its predecessors, or violates the fatigued insulator, or fuses the degraded diode and POOF! - there goes the power supply.

Which particular parts of the computer are most vulnerable to damage if I get a 'surge'?

The power supply is supposed to accept the brunt of the surge, and in the vast majority of cases it will, then it'll fail, and nothing will happen to the rest of the PC. The power supply is so good at its job, in fact, that most of the motherboard failures I've seen attributable to surges actually came through an external port - ethernet, serial, modem, cable, DSL, TV tuner, etc. One of the benefits of wireless is fewer chances for conducted surges to cause problems

Once any one component in the computer is determined dead due to a surge, you might as well write off the rest of the components as flaky. Even if they test ok, the surge may have degraded various cmos chips enough that a regular power fluctuation may affect operation and cause an error. Unless your data is worth nothing, it's usually best to chuck it all once anything other than the power supply shows a problem.

Replacing your surge protector YEARLY

Also, keep in mind that surge protectors, in their most common form, use Metal Oxide Varisters (MOVs) for protection. These are specialized devices that temporarily break down (conduct) in overvoltage situations, shunting the surge to ground.

The problem is that this action damages the MOV. After a year of normal surge abuse, they don't protect as well, and essentially wear out. Some surge protectors use more advanced techniques, and may last longer, but if you don't know then you should consider replacing your surge protector (even if it appears to be operating fine) every year or so.

UPSs that offer bypass mode (ie, the AC goes straight through when the AC is fine) only protect against surges as well as a regular surge protector does. They do more for undervoltage and overvoltage conditions, but only true online UPSs that actually convert the power twice (120V --> 48V --> 120V for instance) can guarantee their surge protection. They provide better surge protection than MOVs. MOVs only break down at a significant voltage (800V, 1000V, etc) so minor surges still get through. An online UPS does not pass any surges that it doesn't generate itself.

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  • Huh, I've had the surge protector under my desk since around the time you posted this answer! I guess it's good that I'm looking for a UPS to replace it. – NobleUplift May 6 '16 at 16:34

The power supply of your computer takes the brunt of all power anomalies. Having worked at a computer repair company for a year, and helped with all sorts of computer problems for the past decade, the most common failures I've seen related to power are failed power supplies and motherboards with damaged electrolytic capacitors.

From what I understand spikes and surges are definitely harmful, but if you look at most power supplies they can safely convert power from 110 to 240 volts to the various DC voltages your computer requires. Thus most spikes and surges within that range are of little problem. Higher voltage spikes and surges of course can cause problems, but they are relatively uncommon.

The big killer of computers is low voltage brownouts. These occur when the power goes out, then comes back on incrementally. Or at times when the power grid is heavily loaded (typical brownout). The power supply will struggle to maintain the load, and cause a variety of power issues downstream.

The motherboard's large capacitors are primarily for power/noise filtering and will heat up when the voltage exceeds their rating. The fluid inside will heat up and in mild cases cause the capacitors to expand slightly (you can see the tops of them will bulge slightly) or in more extreme cases leak and leave a brown or yellow residue outside the capacitor.

My recommendation is definitely to get a battery backup, or at the very least a line conditioner (something that is designed to compensate for brownouts or switch off if the voltage drops below a threshold). The unit will add extra power usage to your overall computer power usage, due to keeping a battery charged, etc. But it will pay for itself both in protecting equipment in the event of a power problem, and certainly in the course of saving you potential hours of lost work on a project you didn't save before the lights went out.

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  • Bulging capacitors on the motherboard are generally caused by operating at too high a temperature for too long. Typical electrolytic capacitors are only rated for 4,000 hours at 60C, which is often exceeded inside the computers of most power users who fail to adequately vent their PC. The power supply should not be allowing over or under voltage conditions on the AC line to affect the power output of the power supply, but cheap power supplies might not be up to par... – Adam Davis Feb 25 '10 at 0:28

Yes - I've seen computers get zapped - mostly after blackouts as the grid comes back online.

I've been led to believe that surge protectors do not stack well, that is, if your multi-plug gives a surge guard, and you plug one into the wall, you will have less protection.

I've started running my guards in parallel - (one guard per device) as I've recently dealt with cheap hardware breaking other devices. I don't know if this helps, but it makes me feel better.

If you're really serious, it's worth putting a UPS (uninterrupted power supply) in-line with your major computer, letting it shutdown cleanly.

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  • A long time ago power surge fried my PSU. ~3 months later after another surge one of my HDD's died. That made me 'reeeeally serious' :] I've bought UPS and live happily since. – Kirill Strizhak Aug 31 '09 at 12:38
  • if you were to put a meter on the line as the power is restored you would find a low voltage situation not a spike. I believe that low voltage (Brown out) isthe greater threat to your electronics. – Brad Sep 4 '09 at 15:36

A surge protector is more than just an apparatus for turning one outlet into six – it plays an important role in electronic device maintenance, such as protecting your laptop. how a surge protector works, we need to define an electrical surge. Think of the flow of electricity as the flow of water running through a pipe. Water moves from one end of a pipe to the other end due to water pressure – water moves from high pressure to low pressure. Electricity operates in a similar way, moving from areas of high electric potential energy to areas of low electric potential energy. In this case, it’s from one end of a wire to the other end. Voltage is a measure of this electric potential energy – more specifically, the difference in electric potential energy. When the voltage increases above the norm for at least 3 nanoseconds, it’s called a surge. If the surge is high enough, it can cause wear and tear on your electronic devices, or in severe cases even destroy them.

Let’s go back to the water pipe example. If the water pressure within the pipe is too great, the pipe will burst. The same thing is true for electrical wiring. If the voltage of the wire is too great – meaning the difference in electric potential energy from one end to the other is too high – then the electricity will surge through. This heats up the wire, and if hot enough it can burn, rendering it useless.

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    +1 That's a good explanation that is clear and easy to understand, but I edited out the irrelevant link. – karel Sep 25 '15 at 11:14

All of you focused on the power supply but surges can back track from external audio systems connected by RCA cables. Even worse, if you have a TV/Capture Card, the antenna coax can carry the surge. Your cable modem can send in a spike as well.

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Everything. Every little piece could be damaged. But it is really rare occasion. I personally never saw a computer damaged this way but my friends were telling me stories how that happened to their friends.

I have also heard of the stories how static electricity can kill your computer, like that time (in a band camp :) when one person plugged headphones into running computer and that fried a motherboard. I however still do plug in my headphones into live system :)

If the power outages are rare, you'd be fine by disconnection your computer from wall socket and network cable during bad weather. If they are happening often, then I'd suggest to by an UPS. Still I don't think your computer will be fried by voltage spike before it gets outdated and then you'll be happy to have a reason to upgrade it :)

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  • I disagree with that 'rare occasion' part :] It depends on where you live, I guess. That happens with some of my friends each 1-2 years. I tell them to buy UPS all the time, but they think it's too expensive... Yeah, right - a fried MoBo or dead HDD is way better... – Kirill Strizhak Aug 31 '09 at 12:43
  • I live in Sydney, AUS... Also does it matter how much you spend on a surge protector? they vary so much in price! – andrew Aug 31 '09 at 12:51
  • I also live in Sydney and I don't use any surge protector :) If you are really afraid, just unplug you computer from the wall socket and from the network cable during bad weather. I don't think you computer will be damaged before it gets outdated anyway. – vava Aug 31 '09 at 13:04
  • If you're going to buy a surge protector, look up reputable reviews done by those that actually test the surge suppression capability. While I probably wouldn't pick the cheapest one off the shelf, higher price does not necessarily mean it better at surge suppression than a cheaper one. – a CVn Aug 4 '14 at 18:05

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