Computer switching off

[JesseJ1935]

This time its my son-in-law thats in trouble.

After his computer, a Heinz 57, has been on for about half hour it switches itself off.

I've had the side off and it does seem to be getting rather hot, though the CPU fan is working. The PSU is warm but not too hot to touch.

I suspect overheating might be the cause but before lashing out any money I would appreciate any advice that you experts may care to give.

I am told the PSU was renewed approx. 12 months ago.

This problem only started a few days ago, until then everything was fine.

Thank you

[djohn]

PSU's can get quite warm when the machine is running a few applications or something intensive like a game or some screen savers even, [Tropical fish aquarium for instance].

Do you know how to access the system BIOS? If so, then turn the machine off after about 20 - 25 minutes, reboot, enter the BIOS and see what the temperature of the system and the CPU is. There should be a reading of both usually under Health status or similar heading. Also, try running the PC with one side panel off and a desktop fan blowing cold air onto the motherboard for a while, see if that extends the time period before it shuts down.

If you can try the above, let us know the result of the desk top fan blowing on the system and the reading of the temps from the BIOS we can advise further. :)

[andsome]

EVEREST will give you the temperatures without messing about inside, and it's FREE.

EVEREST

[djohn]

andsome is correct, but it will not be as accurate as reading direct from the BIOS. I also noted that you have already had the side panel off your sons machine and therefore would not see it as a problem. :)

[JesseJ1935]

Thank you for your replies.

One small update, the computer runs OK with the side off, its not until the side is put back on that the trouble starts so from that I assume that it is definitely overheating.

I will check the temperatures in BIOS and report back asap.

Thanks again.

[andsome]

Are the air vents free from dust, and is the computer in a tight area without airflow round it?

[-pops-]

There is a common myth that operating a computer with the side removed but without an external fan, as suggested by Djohn, will allow it to run cooler. If this does happen, it proves that there is something fundamentally wrong with the ventilation system.

The most important fan is the one attached to the heatsink on the CPU.

In addition, ensure that you have sufficient case ventilation (case fans) working correctly. There should be at least one at about CPU height drawing air OUT of the case. If you have a second case fan, this should be sited towards the bottom of the case at the front drawing air INTO the case.

If there is only one case fan, ensure that there is free passage of air from outside the lower front to upper rear wher the case fan is.

If you are using more than one case fan, always balance the number and power of fans drawing cool air into the case with those blowing hot air out.

[JesseJ1935]

I have now got the temperature readings using both methods.

With Everest I took note every 5 minutes until the computer shut down, they are as follows:

After 15 mins. Motherboard 54C

CPU 54C

HD 34C

After 20 mins. Motherboard 56C

CPU 56C

HD 36C

The CPU Fan was running at 3516/3553 RPM

After 25 mins. As for 20 mins except the HD at 39C

After 30 mins Motherboard 57C

CPU 57C

HD 41C

At 35 mins. immediately before it shut down

Motherboard 58C

CPU 58C

HD 45C

I went into BIOS on starting up again and the readings were:

System 59C

CPU Surface 59C

CPU Core 100C

I had a look round while in BIOS in case there was anything that may be relevant, all I could find which might, or might not, help is

CPU Shutdown Temperature Disabled

Shutdown when CPU Fan fails Enabled

CPU Warning Temperature 70C

I've also found out what motherboard it is, thanks to Everest. Its an Abit KD7 (-RAID) version 1.x

AMD Athlon XP 1700+

Seagate HD ST 360021A 60GB

The PSU was quite cool, no more than warm to the touch.

All air vents were recently cleaned out, as was the rest of the computer, and there is no dust inside at all. One side has nothing against it at all, the left hand side looking from the front. The opposite side is close to the side of a fridge/freezer, about half to 1 inch gap. No additional fans are fitted.

Hope that is of some help to you.

[djohn]

There seems to be some confusion regarding my suggestion to try the PC with the side panel off. I would not recommend running a PC this way for any length of time, it was just to test with a desktop fan blowing on to the motherboard/CPU to see if it was an overheating problem.

Once confirmed by using the method I suggested, and with a little more information from the BIOS reading we can then suggest the best way forward. It has now been proved that it is indeed a cooling problem. Taking into account the remark that its a Heinz 57 model :) we could still do with a bit more info.

It may be that the CPU is overheating, BIOS readout should confirm or not on this, or it may be due to the PSU, or even the memory, or graphic card that is causing the problem.

pops is correct in saying that a PC will/should not generally run cooler with the side panel off, much better to sort out the cooling of the system by using the correct amount/size of exhaust fans, and if required, a fan mounted low at the front to draw air into and the system, preferably over the motherboard.

[Edit] JesseJ1935 has provided the required information while I was typing. Must learn to use more than one finger! :blush:

[djohn]

AMD 1700+ can run to 90 degrees, but this is the maximum and under normal use should never reach anywhere near that temp, 46 - 52 degrees is around the correct operating temperature for this CPU. Seeing that the BIOS is set to shut down at 70 degrees, it appears that your sons CPU is exceeding this.

First thing to check is that the heat sink fan is running and clear of dust, check that the heatsink itself is clear of fluff and seated correctly. Has the heatsink been moved recently? if so did he make sure to seat it fully and use a thermal pad or paste, [Not both] on the base of the heatsink where it makes contact with the CPU core.

[-pops-]

Your core temperature of 100C is too high. It is most likely this that is causing the shutdowns.

Were these measurements taken with the side on or off, with an external fan or without?

If your fans are operating correctly, I would now suggest that the contact between the CPU and its heatsink needs looking at.

Do you know if there is thermal paste on the CPU/heatsink junction? Even if you don't know, what I suggest is that you remove the heatsink and VERY carefully clean the mating surfaces of both CPU and heatsink (use a soft cloth and a pure solvent such as lighter fuel) before applying a VERY thin layer of thermal compound such as Arctic Silver to one surface and re-assembling the combination. The heatsink must be very tight against the CPU. Do not use a lot of heatsink compound - too much can be worse than none at all.

[JesseJ1935]

The side was on. I put it on so as to duplicate as best as I could the problem, which doesn't occur with the side off.

As I understand it, bearing in mind a small language problem (both he and my daughter are totally deaf, I can understand her most of the time of course after 42 years experience, but not him)

He recently, about 1 month ago, took his computer to his son, who lives around 450 miles away, for some remedial work which he didn't particularly want me to do for reasons that will become obvious later in the story. His hard drive C partition, set at only 5GB, was full though the D partition was nearly empty. He wanted his son to do a reinstall of XP Pro and various games, and this is why he didn't want me to do it, his son had all the C.D.s for some unknown reason. Other work that was carried out at the time included cleaning out the innards. Apparently he also removed the CPU fan, cleaned it and regreased it before fitting it back in. What he used on it I have no idea.

From what you have said it looks as though this is the cause of the trouble. I await your advice but it looks as though I am going to have to clean and grease the fan again. Do I need to change anything in BIOS as well?

I am very grateful for your help as I'm sure he is.

[-pops-]

Instructions for the correct application of Arctic Silver are given here http://www.arcticsilver.com/arctic_silver_instructions.htm

I mention this proprietary material as I use it myself but there are others. The application methods for all of the pastes are the same.

[djohn]

The link pops has given will explain all about using the paste, pops still builds quite a few machines, so by following his advice you won't go far wrong.

No, you will not need to change anything in the BIOS and it does sound as though the heat sink has been off the CPU while it was undergoing cleaning and formatting. Again as pops mentioned above, "Don't use too much paste, too much can be as bad as none at all". Also, make sure that the heatsink is set down nice and square on top of the CPU when re-fitting. Good luck and let us know how you get on please. :)

[JesseJ1935]

Thank you again for all your help and advice. I will report back when job is done. Problem for me at present is getting the grease, the nearest computer shop is 45 miles away, but that's my problem of course. What comes of living out in the sticks, its got its benefits as well though.

[-pops-]

If you're in the UK, PM me your name and address and I'll send you a tube of heatsink compound.

It won't be Arctic Silver but one of the materials supplied by Zalman for their heatsinks.

[JesseJ1935]

Report.

I've just finished with my son-in-laws computer, aided, I'm very pleased to say, by another son-in-law who knows more than I do.

The heatsink was removed and found to havw deep scratches in the copper face, presumably his son who had looked at it recently used a screwdriver, or other metal object, to remove the old gunk. A patch was put onto it after cleaning it properly and an attempt was made to fire it up. No chance, the computer came on for a few seconds then switched off, and this is why I was glad my other son-in-law was present. He tried just about everything, taking the RAM out and cleaning it, etc. but no joy. Anyhow to cut the length of this story down, more by luck than anything, the fault was tracked down to the reset button. Every time he tried to boot it reset, the switch has now been disconnected from the motherboard. Went into BIOS when we eventually got it going and the temperatures were:

System 56C

CPU surface 54C

CPU Core 72C.

We now suspect the PSU as that is blowing hotter than it was.

Any further comments/advice/suggestions gratefully received, meanwhile very many thanks for all your help, it is greatly appreciated.