Computer switches itself off

[ROF]

In the US factory built systems must be tested to meet FCC standards for emissions. You home built system may not comply and the ability to test for this is beyond the equipment normally available. (Obviously if it kills your TV picture it doesn't comply).

Factory built systems are normally tested to the standards of Underwriter's Laboratories for safety including shock and fire risks. A home built machine, even with UL rated components may not be risk free.

Another great reason to keep the cover on your computer and to consider purchasing an LCD screen. You will be better shielded from electric fields which can cause headaches, hallucinations, depression, aching feelings and so on.

I have a friend whose kid was always having headaches just before going to bed. One night after his kid went to bed we sat in his place on the living room floor playing his Sony Playstation. After just an hour or so I started getting a headache and my friend was not feeling well either. We took the playstation next door and found it was giving off high levels of EMFs even inside it's sealed case. When we took the cover off and tried it the spikes were so high after just a few hours I bet it would have killed us. We never could pinpoint the cause but found other playstations did not exhibit this problems. He bought another playstation and the problems went away as the other device went into the trash.

[offline]

consider purchasing an LCD screen.

..or just get an MPR II or TCO rated monitor, case & power-supply. In some countries you can rent an EMF meter from your government scientific or environmental health organisation. Some local electricity utilities have a service where they will come out and test your whole home/office.

Currently, two measurement and emission guidelines for monitors have emerged from Sweden. One, known as MPR II, prescribes limits on electric and magnetic field emissions in the ELF and VLF ranges, as well as the electrostatic field. A more recent and more restrictive standard, promoted by the Swedish Confederation of Professional Employees (TCO), limits monitor emissions also, and was expanded in 1995 to address the entire computer. TCO '95 includes guidelines for energy consumption, screen flicker, luminance and keyboard use.

Emission limits prescribed by MPR II and TCO follow:

Electric Fields
MPR II TCO
Frequency Range

Static Field +/-500 V +/-500 V
ELF 5 Hz - 2 KHz (Band I) < /= 25 V/m < /= 10 V/m
VLF 2 KHz - 400 KHz (Band II) < /= 2.5 V/m < /= 1 V/m
Above 400 KHz none none
Magnetic Fields
ELF 5 Hz - 2 KHz (Band I) < /= 2.5 mG < /= 2.0 mG
VLF 2 KHz - 400 KHz (Band II) < /= .25 mG < /= .25 mG
Above 400 KHz none none
MPR II measurements are taken at a distance of 50 cm (approx. 20 inches) around the monitor, at 3 levels of 16 points each.

TCO measurements are taken at a distance of 30 cm (approx. 12 inches) in front of and 50 cm around the monitor (except for Band II magnetic fields and the static field, which are measured at 50 cm in front of the screen).

If you feel like you are getting a cold (flu like symptoms) after an hour or so in front of your computer, then you should check it out.

[mikesbytes]

Appreciate all of the responses - thanks guys.

I made the satement about not being hot before I found the monitoring settings. It's pretty clear that the problem is a hot cpu. Can't find anything in the bios about temperature/shutdown. There is an overclock setting 0%, 5%, 10%, 20%, 30% but its set to 0%.

If its not dusty, I might be lazy and take it down to the Local Computer Shop (LCS) and get them to put in a new fan. Should I fit a genuine one, or an aftermarket and if aftermarket, which one?

And while I'm down at the LCS.....

[budz]

Appreciate all of the responses - thanks guys.

I made the satement about not being hot before I found the monitoring settings. It's pretty clear that the problem is a hot cpu. Can't find anything in the bios about temperature/shutdown. There is an overclock setting 0%, 5%, 10%, 20%, 30% but its set to 0%.

If its not dusty, I might be lazy and take it down to the Local Computer Shop (LCS) and get them to put in a new fan. Should I fit a genuine one, or an aftermarket and if aftermarket, which one?

And while I'm down at the LCS.....

Clean out the dust from the fan on the heatsink then boot up the pc and check the temps again in the BIOS. If the CPU reading is still high temps then it's your heatsink and cpu. Getting just a fan will not make that CPU temp lower if the thermal paste on the heatsink is the wasted and cracked. Then have the pc shop remove and clean the cpu and heatsink then apply new thermal paste.

[King Ghidora]

My $.02 on the cover issue.
I had one case that had mounts to allow you to install a case fan to blow across the hard drive rack, great idea but the back of the fan would be right against the solid front wall of the case so no air could flow through it. This actually contributes to the heat problem as the fan itself becomes another heat source.

LOL I have a case like that. It has these small holes in the front of the case where it looks as if it draws air but there is a solid wall behind it between the holes and the fan. I disconnected that fan the first day I bought the case. There are some really insanely bad designs out there for cheap cases. I always redesign mine myself so I know I have iar pushing in and air pushing out close to the processor. I don't have a lot of problems with hard drives and heat but processors and video cards must have air flow.

I didn't meant to imply that this guy should just look at case issues. He obviously has a big problem with his CPU running at egg frying temp. No doubt he is having crash after crash. His CPU fan is probably failing. I was giving more general advice about heat in my previous post.

It pays to get a really good CPU fan. Get one designed specifically for your CPU. You can get some mighty weird things going on when the heat is on like this guy is experiencing.

oldandinthe way is certainly right about magnetic problems playing havoc with stuff. I have had systems where I had to move the speakers around to keep the monitor from being altered by the magnetic field of the speakers. I'm sure all of us old timers remember problems like this. I haven't had too many problems of this nature for a few years though. Something else to watch out for if you build your own is that some PCI cards may have parts that stick out too far and come too close to other cards. A person might find out that electrictity sometimes follows the path of least resistance which may mean flowing through another card instead of staying in the right card. I've seen cards that had parts that touched other cards next to it so you couldn't put any cards next to it at all.

FWIW a case won't shield any EM spikes. Nothing shields magnetic energy except lots of lead. If your equipment is producing too much of an EM field then you really need new stuff.

[mikesbytes]

Fitted a new cpu fan and so far no problems. Probably could of got away with cleaning it and getting it reseated, but it was only $25 including labour, so why bother.

Thanks for your help everyone.