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Computer Software => Windows => Topic started by: tuftedduck on September 03, 2008, 11:23:53 AM

Title: power cut conundrum
Post by: tuftedduck on September 03, 2008, 11:23:53 AM
Morning, I wonder if some kind soul can advise.

Yesterday afternoon we had a good going thunder and lightning storm, with very heavy rain.

After that went over, I booted up the PC and was happily reading away at this site when we had a sudden power cut, and of course the PC was switched off in a "wrong" manner.

When the power came back, I rebooted expecting to get the warning message that "Windows had shut down in a wrong manner" ( or whatever the correct wording is ) and being presented with the options to "start normally", "last known good configuration" etc etc.

But, Windows started normally of it's own accord and the only sign of the previous trauma was a pop up from my browser asking if I wanted to resume my last session or start afresh.

My question is............why did Windows start up normally and correctly ? I had always thought that after an uncontrolled shutdown, Windows went into a huff and was reluctant to play again without some coaxing.

Not complaining, just curious.
Title: Re: power cut conundrum
Post by: dave.m on September 03, 2008, 11:35:29 AM
TD,
Not sure of the true answer . . . . but . . . as you were only browsing, you were probably not using any Windows files and folders so none were 'open' when it suddenly shut down. As such, it would not have any 'cleaning up' to do and so just opened as normal.

dave
Title: Re: power cut conundrum
Post by: tuftedduck on September 03, 2008, 07:09:22 PM
Thank you for your comments, which are probably correct.
Won't worry about it any more.
Title: Re: power cut conundrum
Post by: dave.m on September 03, 2008, 07:15:02 PM
TD,
It has happened to me a couple of times when the 'Manager' has unplugged my extension lead to put the hoover in.
Each time I was using Firefox and after rebooting normally when I wrestled my plug back, all that happened was Firefox asked if I wanted a return and when I clicked OK it reopened with all the tabs and sites still there.
I think it is just XP getting touchy if it is doing something and gets interupted.
Never had a problem afterwards when it occured so don't let it worry you.
dave
Title: Re: power cut conundrum
Post by: Floydoid on September 03, 2008, 07:17:51 PM
The only time I've had a problem is when windows has failed to load properly, then on rebooting it asks what you want to do (start normally, start in safe mode, etc).  As I recall 98SE used to be far more touchy after a crash/power cut.
Title: Re: power cut conundrum
Post by: oldfogy on September 03, 2008, 09:23:17 PM
TD,
Not sure of the true answer . . . . but . . . as you were only browsing, you were probably not using any Windows files and folders so none were 'open' when it suddenly shut down. As such, it would not have any 'cleaning up' to do and so just opened as normal.

dave
OK, so I'm a bit late answering, but I too was going to say the same as Dave when first reading your post, but he got there first. :sleep:
Title: Re: power cut conundrum
Post by: tuftedduck on September 04, 2008, 10:01:29 AM
Thank you, OF, for the further comments.

The odd thing is that whilst that which I was expecting yesterday did not occur, and the PC booted normally, it did occur when I booted today.

I am in despair with this machine, and am not getting any sleep nor enjoying my days wondering and worrying about what is going to go wrong next.

If it were not my only means of communications with my family abroad, it would go in the dustbin.

I'm too old for this (eighty-seven years too old) and cannot take any more......don't know what to do. If only I still had my hearing, I could use the phone instead.
Title: Re: power cut conundrum
Post by: oldfogy on September 04, 2008, 12:24:57 PM

The odd thing is that whilst that which I was expecting yesterday did not occur, and the PC booted normally, it did occur when I booted today.

I think the problem is "thats computers for you"

When this type of problem occurs, I think the best thing to do is always re-start the PC a couple of times before getting down to any type of work.

But seriously, since I stopped tinkering to "try" and improve things my PC has been behaving quite normal.
(if there is such a thing as normal).

Don't get me wrong, I do still load various bits of software and tinker to follow suggestion/s, but as soon as I have finished, my PC is usually re-ghosted back to the way it was previously.
Title: Re: power cut conundrum
Post by: soms on September 04, 2008, 01:00:26 PM
Sounds like you were quite fortunate there TD.

My personal experience of power failures is that the NT based systems are quite resilient and will boot up OK and perhaps produce the "serious system failure" message or whatever it is. However Windows 9x PCs sometimes fair a little worse and I have had one where Windows needed to be reinstalled.

Something I do on the XP PCs here at home is to disable Write-behind caching on the hard drives.

Write-behind caching is a Windows performance feature wherby it will delay/queue disk operations to improve system performance.  This can be a problem when you say modify or a save either consciously or the system may be doing something and the operation is stored in RAM and delayed as oppsoed to committing it straight to the hard disk in real time.

The idea is that this improves Windows performance, as it will spread the work load on the hard drive using this method. However, if the power fails before the changes have been fully committed then data loss and corruption may occur which can be problematic depending on what the system/user has been up to.

Obviously this isn't such an issue on a laptop where a battery will instantly take over if the mains fails, but on a modern PC you are better to disable it with the hope of trying to safe guard your data and you will not see any real performance loss.

Of course, if the power fails whilst the disk is being used, data loss and corruption may still occur and if your really unlucky drive damage/failure is possible where the mechanics simply grind to a halt.

I welcome other peoples view on the issue but I would recommend disabling write-behind caching if your PC performs fairly well.

It can be disabled  (Windows 2000/XP) in System Properties > Hardware > Device Manager > Disk Drives > [your hard disk] > Properties > Policies and you will see a check box for Write caching.
Title: Re: power cut conundrum
Post by: Floydoid on September 04, 2008, 01:19:03 PM
I've found that enabling write-behind caching seems to improve the overall system performance.

Other performance tips can be found in these excellent tweak guides:

http://www.tweakguides.com/TGTC.html
Title: Re: power cut conundrum
Post by: soms on September 04, 2008, 01:44:04 PM
I've found that enabling write-behind caching seems to improve the overall system performance.

Other performance tips can be found in these excellent tweak guides:

http://www.tweakguides.com/TGTC.html

If you find it helps then you might as well use it...

It was just I saw little benefit and feel I have a little more peace of mind.

Out of interest Floydoid what is your HDD interface? I suspect it makes more of a difference on IDE disks where the interface rate is more of a bottleneck than SATA-II disks.

(Not meaning to drag the thread off topic btw)
Title: Re: power cut conundrum
Post by: Floydoid on September 04, 2008, 03:41:14 PM
I have two IDE drives, both on the same cable.
Title: Re: power cut conundrum
Post by: tuftedduck on September 04, 2008, 03:48:00 PM
Thank you all for your further comments and advices, my apologies for the delay in responding.

I suppose the safest way to go, in terms of power outages, is to have an UPS unit, but I believe they can be fiddly to set up and configure and that there are complications in choosing the right one to match with the PSU etc.

Disabling write-behind caching may be an option, especially as I do have old steam driven IDE drives but, and in referance to OF's comment above, I don't like to do too much fiddling and tweaking..............not expert enough to understand the consequences of doing such a thing.

Will see how things go with this machine, if it goes wrong again I will be going back to the quill and ink.
Title: Re: power cut conundrum
Post by: oldfogy on September 04, 2008, 04:12:45 PM

1. I suppose the safest way to go, in terms of power outages, is to have an UPS unit,
2. but I believe they can be fiddly to set up
3. and configure
4. and that there are complications in choosing the right one to match with the PSU etc.


1. Yes
2. No,
3. No,
4. No.

I use Belkin UPS, just plug the UPS into the mains and plug the PC into the UPS. (job done)
I don't use any of the software that "can" be used.

Although they can be configured to use various aspects, you do not need to.

All you need is one that is strong enough to run your PC, "say 300 watts"
Title: Re: power cut conundrum
Post by: tuftedduck on September 04, 2008, 04:22:43 PM
Aha, simple as that.  ;D

Ok well worth parting with some pennies for that, thank you.
Title: Re: power cut conundrum
Post by: soms on September 04, 2008, 04:48:13 PM
UPS have become cheap these days and you don't need a hugely powerful one.

Just remember to count all devices you want to protect when thinking of the required power output, say the computer and monitor.

The ratings of computer PSUs can be a little misleading, as when it says 300 watts or 500 watts etc that is the maximum power the PSU can provide to the system components, and is not the actual consistent output.

Most systems use between 70 and 150 watts depending on the specifications of the machine and if it is idling or under load (a high end gaming PC would use more than that and the less efficient the PSU is the more power it consumes).

I have one of those Maplin power meter things so I know that when playing graphically demading PC games my PC is using around 120 watts + the monitor.

Beware though to go for a decent UPS with a decent warranty. We  bought some Belkin UPS and they all failed within two years. Whilst Belkin offer a lifetime garuantee, it may not cover the battery, and we couldn't be bothered to send them back to Belkin given the cost of postage compared to the £20 each we paid for them.
Title: Re: power cut conundrum
Post by: stevie on September 04, 2008, 05:29:39 PM
They also act as Surge protection as well.

I`ve got 2 1200VA UPS`s, One which should cover My PC, 40"TV & Sky box & the other for my Main PC.

I`m considering Purchasing a 2000VA UPS for my Fishtank so that the filter will continue running in the event of a power outage.

They will allow you a chance to save & shut down everything safely......& I hope save any damage to things.

There maybe other uses folks can put them to, use your imagination.... A portable DVD player, a small LCD TV, they`ll run these for a little while dependent on the VA rating.

Batteries shouldn`t prove to difficult obtain when then fail, I believe they are Lead acid gel type batteries (at least in the Bigger & Heavier UPS`s) so similar to those in Alarm panels, so they should last for years.
Title: Re: power cut conundrum
Post by: oldfogy on September 04, 2008, 05:38:24 PM

There maybe other uses folks can put them to, use your imagination....

Prior to installing one on my domestic lighting circuit, I used to use one on a table lamp in the living room, which lasted for ?? hours. (8 Hrs +, never got around to actually see how long it would last).

The battery should last "Years" and not really worth replacing because of the cost if it's only a cheap UPS to begin with.
Title: Re: power cut conundrum
Post by: tuftedduck on September 04, 2008, 07:13:50 PM
Been having a look round ebuyer, maplins etc........what a huge choice and such a wide range of price.........will have to take time and read up on some reviews.

Do these things get very hot..........is it safe to have them on the carpet under the desk or should they be "up top" ?
Title: Re: power cut conundrum
Post by: roseway on September 04, 2008, 07:21:15 PM
I've got a 650W Belkin UPS, and it doesn't even get warm with the fairly low load on it. Do be aware though that a UPS won't keep your PC running for very long. The normal arrangement is to install the included software, which will automatically shut down the PC properly if the mains fails for more than a small time.
Title: Re: power cut conundrum
Post by: oldfogy on September 05, 2008, 12:16:21 AM

Do these things get very hot..........is it safe to have them on the carpet under the desk or should they be "up top" ?

They can and do get  a "little" warm but should not be any problem.
Both of mine have been on the carpet for about 2 years now.
(one in the lounge for the laptop & one in the study running "loads of stuff")

Yes ok, not much point if I'm not here without the software, but in my case I don't want to pay Belkin £26 for their lead.
Mine did not come with the lead as they were second hand.
I did try making one according to their wiring diagram but blew up the PSU.  :lol: