Any computer wizards out there?

[BMCC]

I've ran a full scan on my Mcafee internet security (just updated) and it never found anything, Maybe Mcafee's just crap?

I've downloaded 'Core temp' so I can keep an eye on the CPU temp. It will bring up a notice if the core temp goes towards red (90 degree C I believe) so that will rule out faulty fans.

I'll need to look into the faulty PSU. Anyway to tell if it is this via an event log or is it just replace and see?

[indigolemon]

Only thing I can think of is to unplug anything you're not using a lot (DVD drives, TV Cards etc) to take some load off the PSU and see if it still falls over. Apart from that, you'd need to get it on a test bench to check it properly.

Back when I still used Windows I had bought this: http://www.cpuidle.de

It implements a proper low power idle mode on your PC. Dropped average temps by 10c for me

[eDaniel]

Reboot in Safe Mode and try to keep the PC in this mode just to see if the problem disappears in this case.
Other than this, the PSU might be faulty as suggested by the other members. You can take a multimeter and then measure the voltages of your power supply. Take of the HDD molex connectors and measure the voltage between the black wire and the yellow wire it should be 12v +/- 5%. Then check the red/black wire for 5v +/- 5%.
Max/min values for:
5V -> 4.75v - 5.25v
12V -> 11.4v - 12.6v

[indigolemon]

Reboot in Safe Mode and try to keep the PC in this mode just to see if the problem disappears in this case.
Other than this, the PSU might be faulty as suggested by the other members. You can take a multimeter and then measure the voltages of your power supply. Take of the HDD molex connectors and measure the voltage between the black wire and the yellow wire it should be 12v +/- 5%. Then check the red/black wire for 5v +/- 5%.
Max/min values for:
5V -> 4.75v - 5.25v
12V -> 11.4v - 12.6v

That won't work on most modern power supplies, as they're switched so they'll only show power if they are under load. Worth a shot just in case though

[Rich]

Just been reading up on a few forums, it may be overheating or an issue with the PSU after all. It appears Windows has come on quite a bit since xp... last time I had any such issues my PC would just BSOD &/or switch off. I do have Windows 7 on my laptop but it has been very stable to date so I'm a bit behind on troubleshooting advice.

I don't know what form factor your machine is or what kind of load it has but this is a decent good price PSU which may be worth testing out:

http://www.cclonline.com/product/78484/ ... -/PSU0327/

[Gayno]

But how can any faulty piece of hardware initiate a system shutdown procedure?

I'm an IT tech and anything like this I've seen in the past has always been software or virus. It is possible if his motherboard came with some monitoring software and it's overheating that this is initiating the shutdown, but normally if a CPU hits critical temperature, the system will just shut off.

McAfee IS rubbish! Download and install Malwarebytes and Spybot, then run full system scans using both. If anything is in there, they'll find it.

If you're still having problems after the weekend, I can connect onto your machine remotely and see if I can see anything the logs etc. I promise not to browse your Internet history

[Rich]

But how can any faulty piece of hardware initiate a system shutdown procedure?

That's what I thought until I read up in a few techie forums that a faulty PSU etc caused the issue. Not sure how reliable these sources are or if the issues were permanently resolved by the solutions provided though.

McAfee IS rubbish! Download and install Malwarebytes and Spybot, then run full system scans using both. If anything is in there, they'll find it

^ this!

[judderod]

Have you tried checking the system drive for errors?

I use housecall if I need a 2nd opinion from an antivirus program.

Lastly, you could install SiSoftSandra (download free from Guru3d). That can be set to do stress testing on various pieces of hardware to help isolate the fault.

My money's on a disk error or failing motherboard capacitors (power regulation). If you do take it apart, inspect every electrolytic capacitor (use google images) for leakage, bulging, or split/raised tops.

[Lude-dude]

my experience has been down to faulty components

I have same kinda problem, I was underpowering my pc

bought a new power supply its better, but still happens sometimes, I still think its still underpowered

these new pc & graphics cards are very power hungry

Ive had faulty cd drives, hard drives, usb card readers cause weird problems too

[judderod]

bought a new power supply its better, but still happens sometimes, I still think its still underpowered

I bet that's you capacitors too mate. PSU's start off pretty clean and slowly get more 'dirty' over time, putting out ripple, surge currents, interference, RF, EMI, noise blah blah into your motherboard.

Motherboards are equipped with their own power smoothing - voltage regulators, shunts, capacitors etc. Slowly these degrade over time and can't smooth the power as effectively. Replacing the PSU will help for a while because it will probably be cleaner than an old PSU, but the motherboard will continue to fail.

All decent motherboards these days have done away with the old electrolytic caps that fail and have replaced them with poly that don't.