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PC power cycling on & off

by Romcc / February 19, 2009 11:04 PM PST

Hi everyone,
I need some info & I hope you all can guide me in the right direction.
I have a ThinkCentre PC MT-M running XP Pro w/SP2. It stays on constantly. I've never had an issue of any kind with it. No new software or devices have been installed recently & no changes have been made to its power saving settings in any way.
I came down yesterday & noticed it making a boot noise & then, in about 2 seconds would cycle off. I took off the side cover & noticed the fans would kick on, I could hear my screen get signal & then down it would go. This repeats continuously. It has a LiteOn PS.
Any help would be appreciated.

Thanks much

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Thats and older pc
by darkzenlord / February 20, 2009 4:30 AM PST

It is more likely with the age, you would experience an issue such as this. If this constantly reboots and fails to POST, (before windows) sounds like a hardware issue. (maybe you proc overheated, something like that). If it is getting to windows boot screen, then restarts, your windows is bluescreening and the startup and recovery option is to automatically restart on those types of errors.

So let us know, if it only stays on for like 4-6 seconds before it reboots, that would be failing to post and is most likely a hardware issue.

Let us know!

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PC cycles on & off
by Romcc / February 20, 2009 5:25 AM PST
In reply to: Thats and older pc

I've just had it about a year but who knows how long since its been made right?
Anyway- the on & off cycles are about 1-2 second increments. For 1-2 seconds the fans come on & then 1-2 seconds- they go off. I've had it off since this morning & I just plugged it back in & it does the same thing-continuously.

thanks much- any ideas?


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PC power cycles on & off
by Romcc / February 22, 2009 12:02 AM PST
In reply to: Thats and older pc

Darkzenlord- no- never hear any beeps & the screen remains dark. The yellow LED on the back of the PSU blinks when it tries to boot but its just a blink & nothing more- Thankx to all for the input.


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Sounds like heat to me . . .
by Coryphaeus / February 20, 2009 5:11 AM PST

Blown the dust out of it lately? Especially around the cooling vanes on the processor.

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PC cycling on & off
by Romcc / February 20, 2009 5:22 AM PST

Thanks for the reply but it does it immediately when its plugged in after its been off for hours.The processors have had plenty of time to cool & its about a 2 second on & off cycle. It boots for 2 secs & goes off for two seconds- & this repeats continuously.


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Start unplugging things . . .
by Coryphaeus / February 20, 2009 7:03 AM PST
In reply to: PC cycling on & off


hard drive
optical drive, all
anything plugged into an expansion port, except video card if one is present

Power up. If you get a boot that shows no operating system found, good. Power off. Plug back in in this order, one at a time and power up to test. After each device passes, add another:

hard drive
optical drive
expansion cards

This will be time intensive but you need to find a possible defective device.

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PC cycling on and off
by jlwhit / April 25, 2011 7:57 AM PDT

Just ran into this today (04/25/11) for the first time. This solution did it for me. In fact, all I had to do was remove the RAM and reseat them. Presto!! I'm in business. Thanks coryphaeus!!! Blush

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Clean it
by Dango517 / February 20, 2009 12:29 PM PST

Replace thermal paste/grease. Check your fan connections. (Touch a metal object before you do anything inside your PC tower. Also unplug it.) A faulty CPU
fan can cause an immediate shut down but usually with a warning message. Yours might be shorting out on boot.

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same problem, I think.
by Bruno Carvajal / February 20, 2009 1:05 PM PST

try to do without the back-up battery,if it resolves, change the back up battery inside the back up, if continues go to the power unit, did both, but ended installing a new motherboard. In my case, an old pc. Hope it helps.

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pc power cycles on & off
by Romcc / February 21, 2009 11:54 PM PST
In reply to: same problem, I think.

Tried that but the problem remains Bruno- thankx- according to an IBM site Wanderlust sent me to- it looks like a board problem.

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get a new motherboard.
by Bruno Carvajal / February 23, 2009 7:55 AM PST
In reply to: same problem, I think.

told you, it was the motherboard, prepare to call microsoft because the hard drive will not get along with the new motherboard, at least that was what happened to me and everything was save on windows old but had to reinstall windows again. If it works for you and don't have to reinstall windows again let me know how you did it so that I can learn. Thanks, Bruno

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PC power cycles on & off
by Romcc / February 23, 2009 8:46 AM PST
In reply to: get a new motherboard.

Yes you did Bruno. I don't know which way I'm going yet as I've been told to buy an original OEM for the MB or throw my money to the ponies.
The ones I've seen are pricey so maybe a new PC & somehow figure out how to transfer the HD to a new barebones------------------but I understand that's a pain in itself as well. I'll let you know how things turn out & thanks again.


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Constant re-boot
by wanderlustfl / February 20, 2009 11:10 PM PST

You still haven't said whether you are getting 'post'.
If you are not getting post then follow the options above re the RAM, HDD, etc., although there is a good chance it's either the Hard Drive failed, or a failure somewhere on your motherboard or processor.
Are you getting any 'beeps' ? - If so, how many and in what sort of frequency ?

If you ARE getting post, does it get as far as the Windows screen before recycling ?

If not, then it is still likely to be a hard drive problem.

If you ARE getting the Windows screen, it is most likely damage to the boot sector. In this case, if you've nothing you need to keep, then re-install Windows. If you do need to keep stuff, then at this stage you can decide whether to take it to a repair shop or not. In a repair shop, they can check your hard drive and whether the data on it is accessible. If it is, they can back it up and either re-install, or repair your boot manager.

Have you tried Safe Mode (press F8 during startup) ? You probably have, but it is worth asking. You can use Safe mode to find a restore point to work from.

If you want to try a repair yourself, then there is a way you can repair the boot manager using the Windows CD to boot into the Windows Repair Console. I have done several tutorials for this, but they are for PHP boards. However, I can either provide a link, or attempt to post it here. It goes a bit deeper than the usual 'fixmbr' and rebuilds the master boot record from scratch, using the recovery console. (A short series of DOS commands).

If the Windows CD can't find an installtion to repair then you are back to a possibly broken hard drive.

Did you get recovery CDs with the PC ? If so, have you tried doing a partial recovery ? Or if it has an on-board recovery partition, have you tried using that ? Be careful, though, because if it does not allow a partial recovery/repair option, then you will most likely wipe all your data and installed programmes.

I'll go and look this up and look back later to see how you got on.

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Constant Re-Boot
by wanderlustfl / February 20, 2009 11:36 PM PST
In reply to: Constant re-boot

I see you have subscribed to the Lenovo forums but had no reply posted as yet.
Have you tried following the steps in this page :

(Copy and paste the link into your browser)

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PC power cycles on & off
by Romcc / February 21, 2009 11:51 PM PST
In reply to: Constant Re-Boot

Aha- Wanderlustfl- the yellow light on my PSU blinks momentarily when the system tries to boot. According to the chart on the IBM iste- this indicates systme board which is?????????? Mother board?

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PC power cycling on & off
by Romcc / February 21, 2009 11:01 PM PST
In reply to: Constant re-boot

No post- never gets that far I suppose. I hear no beeps- have unplugged everything possible & plugged up one @ a time hoping to isolate but the symtoms remain unchanged.No screen activity at all- just fans kicking on then off in 2 second on/off cycles.

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Sounds like...
by mwooge / February 21, 2009 11:03 PM PST

You have a hardware problem. A bad or corrupted HD would take longer to crash.

If other troubleshooting dosen't work, try removing your HD and putting it in another computer as the second drive. Back up your important files (preferably twice), then reinstall the HD in the bad computer. You can now try drastic measures which might damage or wipe the HD.

If all else fails, you can now take it in for repair.

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PC power cycles on & off
by Romcc / February 21, 2009 11:58 PM PST
In reply to: Sounds like...

Thankx mwooge- I'll give it a shot & let you know. Thankx for the direction.


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PC power cycles on & off
by wanderlustfl / February 22, 2009 5:10 AM PST

Yup. Unlikely to be your hard drive. If you already did the VGA test (i.e., if your PC uses a Video card but has an onboard chip too, remove the video card and plug into the on-board one. This was outlined in the link I posted before.)

However, is almost definitely your motherboard, only other possibility is the CPU.

If you don't feel capable of doing your own hardware repair and are frightened to waste money on getting a new motherboard wrong, the take it to a reputable repair shop.

You can get motherboard and CPU sets, often with RAM too for prices varying from fairly cheap to very dear. Go for a mid range in your budget, or try to get the same motherboard, possibly from IBM or Lenovo, or see if you can trace it elsewhere. Chances are it may be difficult to find, though, and better to take the opportunity to upgrade a little.

Your present hard drive should work with a new motherboard, and you should not lose any data, although will need to install drivers if it's a different motherboard. Nevertheless, as with anything to do with hardware replacements or software upgrades, back up what you need to keep. The repair shop will probably offer you this service too if you don't have the facilities.

Other option : depending on the age of the PC, it might be more worthwhile to go for a new PC rather than throw a lot of money at the old one. Get the repairs priced, and compare with a new PC. If it's going to cost more than 2/3 of the cost of a new one, go for the new one !!!

You could install the drive in your new one, either as master, making its drive a slave, or as slave to the new one's drive. Depends on whether you've got backups for all your programmes so you can re-install them or not, and whether you want the newer OS (Vista at present).

Good luck !

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PC power cycles on & off
by Romcc / February 23, 2009 4:57 AM PST

Thanks Wanderlustfl- it is my MB. I put another PSU on it- put the HD on another unit, etc- it all points to the MB so I have a look and see what I can find out there.
Thank you & all of you that assisted.


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