system shutdown on its own

Hi,
I am new to this forum and really need help, My computer has been shutting down and restarting on its own since a motherboard replacement. The same kind of motherboard was installed on my system. I have replaced the power supply, a new fan, the hardrive, put in a larger graphic card (Nvidia GS7600 512mb). I have reformatted, updated the drivers and bios for my system and still it shuts down with no error, no warning. There is no malware detection, no virus's. I am at my witts end trying to figure out what is causing the shutdown and how to stop it. I was told to add more memory now...I am currently using 3GB on a 750mb hardrive with a 300GB slave drive. The shutdown happens even without the slave drive..tried disconnecting it and still happens. I have no answers at this point and need some major wiz help.
I would appreciate some input here...:confused

I currently run Windows XP home edition SP2 (5.1 build)
Default system bios
intel pentium D cpu 3.00GHz (2 CPUs)
3070MB ram
418MB used, 4534MB available
DirectX 9.0
Display ..main driver nv_disp.dll version 6.14.0011.6371 english.. 9/17/2007
Mini VDD nv4_mini.sys DDI Version 9

This is all i have for info at this point, if something else is needed that might help please post to let me know...

 

I have no idea what that is...replace standoffs? ...I just reformatted because that is what I was told to do to fix the possible issue with the motherboard...I guess they thought that is what was causing the shutdown problem...regardless of reformatting using the original install discs..it still shuts down...
Please explain about replacing standoffs...

 

Before you do any more you need to localise the cause.

When does the shutdown occur?

Does Windows actually boot normally and work for a while?

Does Windows boot and work without shutdown in safemode or commandline mode?

Does the system boot to bios and stay running with no hard drive attached?

Does the system boot and stay running with another operating system eg win98 or linux from floppy or Windows setup or linux from CD?

 

The shutdown and reboot happens anytime it decides...it boots up normally, then when i decide to use a program..(not always) it just shuts down and reboots...it then will work good sometimes for hours, like now..lol and then when i think its alright it does it again...in safemode i haven't had a shutdown that i can say for sure. I was using the safemode at the time I installed the new hardrive and didn't have a problem. It boots into Windows beautifully but if it shutsdown and reboots on its own i get a error message stating that the system has just recovered from a serious error. This message also does not appear each time...I have not tried to boot without a hardrive?...It did not shutdown when i did the reformatt process and it booted from cd. I do not recieved error messages, but at times my system freezes and i have to do a end task on whatever i am in the process of doing. Yesterday i was installing backed up files from cd to the hardrive , my system froze, my mouse froze. I have had it not want to shutdown at all but not able to do anything either because of the freeze up. In turn i have to do a illegal shutdown and reboot...then its good again for awhile. Frustrating.

 

I noticed that you added a "larger" video card and you also replaced the power supply. Might it be that your power supply does not supply adequate power to your computer? Also, when you run a program your computer stresses a bit too so that might be the problem. Overheating also causes shutdowns for no reason.

 

From your description I would look for a driver problem.
What does it say in the event log?

start>run>typein
eventvwr
or eventvwr.msc

 

i typed in what you said...run etc...there are 3 logs but in the one i opened it states no cd rom...I have 3...i put a disk in and it does see the disk, the drivers are there and are updated . my shutdown has stopped since uninstalling roxio but the cd/dvd drives will not auto play now since uninstalling roxio...Solutions?...fix one problem and led to another..

 

Well i fixed the shutdown problem by uninstalling Roxio 7 but now my cd/dvd drives refuse to auto play. i have tried the microsoft autofix which gave me this...

utoFix [V5.2.3790.67]
Time [2007-10-10 10:26:35]
Microsoft Windows Version [5.1 (Service Pack 2) <2600>]

Test [The Shell Hardware Detection service is running.] - Instance [N/A]:
Result [AutoStart Setting]: OK
Result [The Shell Hardware Detection service is running.]: OK

Test [Policies] - Instance [D:\, Drive Type: 5]:
Result [HKCU\...\Policies!NoDrives]: OK {Absent}
Result [HKCU\...\Policies!NoDriveAutorun]: OK {Absent}
Result [HKCU\...\Policies!NoDriveTypeAutorun]: OK {Present}
Result [HKLM\...\Policies!NoDrives]: OK {Absent}
Result [HKLM\...\Policies!NoDriveAutorun]: OK {Absent}
Result [HKLM\...\Policies!NoDriveTypeAutorun]: OK {Absent}
Result [Driver level policies]: OK {
HKLM\...\Services\cdrom!Autorun (Present) <Allows>
HKLM\...\Services\cdrom\Parameters!Autorun (Absent) <Allows>
HKLM\System\CCS\Enum\...!AlwaysEnable (Absent) <Not set>
HKLM\System\CCS\Enum\...!AlwaysDisable (Absent) <Not set> }

Test [Drive Notification] - Instance [D:\, Drive Type: 5]:
Result [Legacy Notification]: OK
Result [AutoPlay V2 Notification]: Problems {
Service (Silent)
Shell (Deaf) }
>> Repair << [Autoplay V2 Event]
Step: No steps to take.
Result: This AutoPlay setting cannot be fixed. Either the device is malfunctioning, or the wizard cannot determine the problem.

>> Required action: The wizard found problems but cannot fix them -> None

I do not understand this...I also went to microsoft
http://support.microsoft.com/kb/330135 and did what it stated. :cry... My autorun still will not work when a disc is insterted...the drive does however see the disc it just doesn't want to run. I need help please. I am trying to fix this issue on my own but it's not working...:confused

i also went to the link you gave me and did that, no change in cd/dvd drive autoplay....