Gaming Power Outtage Damage to Computer?

[Raiser]

Hey guys,

It was rather rainy / windy in the Lower Mainland last night and I was up with some PC gaming when the power just get konked out.
It turns back on about 10 minutes later, and I assume everything is alright so I turn it on again. Then at the desktop it gets konked out once more.

I look outside and see that the big gray thing (in our lane-way, my dad calls it the transformer) has no smoke or sparks coming from it and the casing has no black marks.
BC Hydro comes along and spends 3 hours fixing / replacing it.

Then I fall asleep and wake up at midnight to see the power is back on.

I don't have a surge protector, so over the course of this affair, how much damage has my computer taken? o.0

 

[Rydian]

Most operating systems cache write data. That is, they store pending writes to disk in memory and flush it to disk in batches. This improves read performance in certain cases. And, in certain cases, write cache will sometimes remain for long periods of time without being flushed.

The consequence of that is threefold:

• When power is cut during a write cache flush, not all of the data is written. Files will remain incomplete, data will be missing, and filesystem metadata will be corrupt or incomplete. This is why filesystem journaling was introduced. Recovery requires a careful analysis of the hard drive to locate and correct corrupted and missing data. This nearly always results in lost files.
• When power is cut before a cache flush, all of that data is simply lost. Files will not be created, they will remain incomplete, and the filesystem will likely be inconsistent. This results in loss of "unsaved" data.
• If power is lost during any kind of read or write operation on a hard drive, there is a small likelihood that there will be physical damage to the hard drive, which, in certain cases, will result in not only loss of data but unrecoverable damage to the physical drive. Hard drive manufacturers work very hard to make sure that doesn't happen, but the risk is still there.

There are other problems, such as inconsistent hardware state (such as a BIOS flash gone wrong) and thermal shock (such as a hot capacitor suddenly getting very cold) that can result in dead hardware.

If you do pick up a surge protector, make sure it's actually a surge protector and not just a "power strip". many power strips people buy aren't actually surge protectors.

 

[Raiser]

Right, thanks Rydian!

The original question was about possible damage due to infrequent power outages. The most likely damage caused by sudden loss of power is damage to the filesystem, not physical damage to the computer. Such damage to the filesystem is usually, but not always, repairable via 'fsck' or other disk utilities.

Damage due to a thunderstorm is often due to the other end of the extreme - sudden increases in the voltage supplied to your computer. A UPS will protect you from these, but so will (to a lesser extent) a relatively cheap surge protector built into the power strip.

Would this be true?
There was no lightning whatsoever, just wind and rain.

 

[Sir VG]

Generally most times when the power goes out during a storm, unless the wiring in your house is crap, your computer should be just fine, barring you (or your computer naturally) aren't turning it back on right away. Usually more damage is caused by turning a computer off and on rapidly. Not saying a storm can't do damage - it just depends on what the storm hits.

 

[Raiser]

Generally most times when the power goes out during a storm, unless the wiring in your house is crap, your computer should be just fine, barring you (or your computer naturally) aren't turning it back on right away. Usually more damage is caused by turning a computer off and on rapidly. Not saying a storm can't do damage - it just depends on what the storm hits.

First time it went out, I was gaming.
After it came back on, I turned on my computer 2-3 minutes after and it *seemed* to have fully loaded to the desktop. Then it went out again.

EDIT: @ Rydian:
If the power was cut during / before a cache flush causing missing / corrupt data, a system restore would theoretically *fix* everything (being system files & registry), would it not?

 

[Foxi4]

The only physical damadge that might occour during an outage is:

A) Burning the fuse/fuses inside the power supply unit. Fixable by changing the fuses.
B) Hard drive damage due to the header smacking againts the spinning disk (small probability of that happening).

MOST of today's power supply units are protected againts power outage. Your REAL enemy would be any large electric discharge (thunder hits the power lines, the local transformer, transformer malfunctioning, whatever other cause), although the likelyhood of THAT happening is minimal.

A power strip with fuses is always welcome though.

 

[trumpet-205]

If you have the money, grab a UPS that has surge protector built in it. UPS will allow your computer to run about 10 mins after the outage, allowing you to shut down your computer properly.

 

[Frederica Bernkastel]

If you have the money, grab a UPS that has surge protector built in it. UPS will allow your computer to run about 10 mins after the outage, allowing you to shut down your computer properly.

I'd just like to add, most UPSs can integrate with your computer pretty nicely, such as giving you a notification and optionally turning off your computer automatically if configured to do so.
EDIT: if you're willing to spend the money, they can become really useful tools.

 

[Rydian]

EDIT: @ Rydian:
If the power was cut during / before a cache flush causing missing / corrupt data, a system restore would theoretically *fix* everything (being system files & registry), would it not?

No. System restore does not actually turn back time like people think it does, and it only affects system things, not user things. A fix is just running checkdisk to fix the filesystem corruption. Any data lost is lost.

 

[twiztidsinz]

The only physical damadge that might occour during an outage is:

A) Burning the fuse/fuses inside the power supply unit. Fixable by changing the fuses.

If your PSU dies and surges, it can cause damage to other parts of the system.

 

[Raiser]

EDIT: @ Rydian:
If the power was cut during / before a cache flush causing missing / corrupt data, a system restore would theoretically *fix* everything (being system files & registry), would it not?

No. System restore does not actually turn back time like people think it does, and it only affects system things, not user things. A fix is just running checkdisk to fix the filesystem corruption. Any data lost is lost.

Yes, I know which is why I mentioned system files & registry. If I system restored then at least those files will remain intact right?
User data I'm not too concerned about as all of my important files seem to be functioning properly.

 

[Rydian]

I'd count on checkdisk before system restore to fix filesystem corruption.

 

[Frederica Bernkastel]

EDIT: @ Rydian:
If the power was cut during / before a cache flush causing missing / corrupt data, a system restore would theoretically *fix* everything (being system files & registry), would it not?

No. System restore does not actually turn back time like people think it does, and it only affects system things, not user things. A fix is just running checkdisk to fix the filesystem corruption. Any data lost is lost.

Yes, I know which is why I mentioned system files & registry. If I system restored then at least those files will remain intact right?
User data I'm not too concerned about as all of my important files seem to be functioning properly.

I believe Rydian is talking about actual damage to both the disk and the filesystem. Two things which are completely ignored in a standard system restore.