PC Shutting Down

I'm trying to get this in before my PC shuts down again, so I have not searched properly. I have an ASUS mobo with WinXP SP2. My PC shuts down at various points. Sometimes it gets entirely through the booting process, sometimes it shuts down before. I took it into a repair shop and they searched for viruses and checked for heat problems (they said they found a virus which they fixed). Sometimes my PC will stay on for two or three hours before shutting down. There is no BSOD, the monitor just goes blank. I have removed most of the peripherals (2nd monitor, printer, extra hds, etc), and I am running with the cover off. I d/led Speedfan and all temps are below 50 C. Sometimes it takes several times before I can boot to a stable system. Would appreciate any help. I will try to get back online long enough to check for replies and search this forum properly.

 

Thanks, I will try that.

 

Have you manged to get the stop code from the BSOD?
Try taking all of your ram out, put one stick in and try again, keep doing this, if the PC doesn't shutdown with one of the sticks in then one is bad. If it shuts down on all the sticks chances are ram is fine and we can look else where but tell me how this goes first

 

Hi Capn,
Thanks for your suggestions. There have been no BSODs (the monitor just blanks), but I will try swapping out the RAM as well.

 

Try booting and running the machine with a nomadic operating system from CD or pen drive and see if the problem remains.
This will help in determining if it's a hardware or software based issue.

 

The RAM doesn't seem to be the problem. I swapped out both sticks, and still got shutdowns. Locating a replacement power supply is my next task.

Interestingly, the PC seems to get more stable the longer it is on. I will try to boot it up in the morning, which takes 4-5 reboots and several minutes. When it finally 'settles in', it will stay on longer (3-4 hrs seems to be the max, though). Also, when I plug in my 1TB external drive into an USB port and try to copy files to it, I nearly always get an instantaneous shutdown. I can read the contents of the external drive, but writing seems to cause a shutdown.

The PC also shuts down in Safe Mode. confused:confused

 

I am not familiar with these, but I will google.

 

Sorry I should have been more specific, I normally use DSL from a pen drive for this sort of thing.

 

Swapped out graphics card, RAM, power supply. Pretty much everything but the mobo. Still have the same problem. Trying to obtain a new mobo. Thanks for the help here.