Random Shutdowns

it can be a heat problem, so check these first :
-are all fans running? cpu, case, power supply
-clean away all dust
-check if the heatsink is seated fully on the CPU, or replace the artic silver on it.

it can be a bad power supply too, can you test with another one.

you can set the system not to reboot, it will give a better indication (hopefully) :
in device manager>advanced tab>restart section click settings and uncheck the "restart PC on errors"

some testing can help too :
Ram : memtest86+ from :   http://www.memtest.org/
disk : do a disk scan for errors

Did u installed any recently installed software or any pathces, remove those, it will solve the issue.

Cheers,
Shan

Shutting down , not restarting  , is it?

if shut down automatically, that could be P/Supply problem
Check the Power supply Fan is operating, ( over heat )
 And check with another P/supply unit (could be Power supply unit circuit problem )

vmaheen, all that has been said already, please don't repeat posts, but read the whole thread.

http://fileforum.betanews.com/detail/SpeedFan/985582286/1

Free app which can help you monitor your fan speed, temperatures, etc...

Just a side comment:
"This cant be any virus as i am using MCafee v9 and that is updated i have scaned my system several times but found no virus."

You cant completely rule out a virus based on this. Your issue doesn't sound like a virus but because you scanned with an updated scanner doesn't mean it can't still be a virus ;)

First data start by holding your windows key down and pressing the break button
this will open your system properties
Click on the advanced tab Look for a startup and recovery click on the settings button
Down towards the bottom make sure the automatic restart is unchecked

now when your system shutsdown it will be caught by a blue screen with the error information
please post the type of error and the error codes which would indicate the exact problem and location
then we can further assist you with your problem

Hey

Check to see if any metal slots (ont he pci cards) are touching the motherboard.  This is an overlooked problem in troubleshooting... sometimes the metal slots can short a connection on the board and be the cause of the sloow performance and then freezing and then restarting after a while.  So check tosee if anything is shorting out the connections.

Hope this helps

Cam

Thanks ..
The system works fine for 7 ~ 8 hours then starts shuttingdown without any event log. This is not a windows based problem as sometime it even shutsdown before loading windows. All the fans are working fine and i have attached another fan with the chasis and that is working fine too. I have cleaned the system with compressed air and the processor heat sink is fine tooo. I havent checked for any shortage will check that. All the automatic restarts are disabled. There is no blue screen error. No error at all and no Event log either.

Additional Information

Scanned the system with mcafee 9 , adaware , sapybot.
New softwares were installed.
No new hardware was installed.
have checked the power supply seems to be working fine.
Changed the CMOS battery.

One thing you could do if you can get into the Operating system which is WIndows XP? Is enable no automatic restart on stop errors.  This way we can identify a problem shuld the blue screen arise.  This may help in further diagnosing the problem

Cheers

Cam

in your case you are on the right path

a simple registry error
open notepad and write the following command including title
then save as (any) *****.reg   then double click to execute
 
Windows Registry Editor Version 5.00

[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\
Explorer]
"NoClose"=dword:00000001

sorry Nobus i didnt read ur comment completly,

Dear  Umairp

can u replace another  power supply unit. as NOBUS says  , try with 350 W ( higher than current P/supply)

( take ur friends one for testing)

did you try what i suggested in my first post?

What type of power button do you have on your case? If it's the type that just spring back.. then you want to check the actually button.
My first suggestion was it's a heat problem/heat sink problem, but those seem to not make a difference.
Sometimes what happens is, the spring for the Power Switch gets stuck and turns the computer on or off by itself with no signs of an error.
I used to have a TV that did this all the time even, and I fixed it by checking and cleaning the button.

M. Saeedi

Now all we need is the stop error to see what the real problem is.

To disable reset on stop errror automatic restart for the computer

1. Right click on My computer and select Properties

2. CLick Advanced tab

3.  Select Settings under Starup and Recovery

4. Under System Failure uncheck Automatic restart

5.  Try to generate the BSOD(Blue screen of Death) Error and write down what it says in the error message.

Goodluck

Hope this is more usefu;

Lanadmin, all that i said in my first post; please read the whole thread before replying !

Sorry, I was helping someone else out so I was jumpin back in forth between these forums.  I apologize :)

Well, if umairp did that in the first post... he should hopefully beable to get the stop error right

Umarip I have a question for ya... "No error at all and no Event log either. "  When you said this in one of your previous posts did you mean there was nothing in the Event log that pointed out an error to anything?  Cause if there are no errors in the event log, its probly a peice hardware problem

Tried cleaning ,checked with alternative power supply but of no use. checked the power button but the problem still remains. I think the problem is with mother board. Thanks all for ur help.

I'll see others can be a hardware problem obviously if there are no errors in your event log then  windows thinks it's doing the right thing at therefore I believe the problem lies in your registry I have a few more scripts for this issue or you can try reading some registry repair software

Hey Akarre

There is a program you can download here for diagnosing system hardware such as your motherboard

http://24.36.20.67/server/files/

Click on files
(username: admin and password is admin)

and click on the file Microscope 12.exe

How this works!

Hey umairp

There is a program you can download here for diagnosing system hardware such as your motherboard

http://24.36.20.67/server/files/

Click on files
(username: admin and password is admin)

and click on the file Microscope 12.exe

Sorry for the doublepost!

I have already disconnected every possible hardware which i could. The problem is in the mother board i think cuz i have swapped the power cables and rams too the only thing i didnt replace is the mother board and the processor.

mer bhi yahi kheyal hai key motherborad mein problem hai dusrey pc mein board or processor laga ker dekho

    Umair

? ? ?

So umairp... did you try using Microscope 12 to diagnose that, because it should tell you if the mainoboard is bad

pc im not sure what the last post is supposed to but

Cheers

Cam

No matter what  you remove the entry will still be in your registry that is bypassing windows command and telling windows to shut down