Computer unuseably noisy in hot weather

I originally posted a question in the Wireless networking section about laptops, because I'm looking at replacing my old desktop, partly because it is increasingly noisy. One poster suggested I describe the problem with the old PC here, to see if it was fixable.

I'm not particularly techie - I have replaced hard drives and power units on computers before, but that's about the extent of my knowledge.

Right - the problem. I use a 4.5 year old Dell Dimension desktop, Pentium 4 Processor. It has ALWAYS been noisy in HOT weather, which I would describe as anything over about 75F. I have just sucked this up in previous years and used it for limited periods of time in hot weather.

I assumed it was the fan, but as it wasn't a frequent issue, never got around to thoroughly checking out the problem.

This summer, it has been getting noisier at lower temperatures - only 70F now (says Yahoo and the BBC) and it's making a racket already.

Vaccuming/dust removal no longer makes any difference.

Bearing in mind that it is 4.5 years old and I don't want to spend large amounts of money on an old machine which has been used quite heavily and will presumably be subject to significant wear and tear, does this sound like something easily solved/reduced?

Barb

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Switched to O2 Standard LLU (from BT) on 3/3/09, Ilford North exchange.

Sorry - an obvious question --

Do you know what is actually causing the noise ???

A fan, hdd or ?

In reply to a post by eebdsirhc:

Sorry - an obvious question --

Do you know what is actually causing the noise ???

A fan, hdd or ?

No need to apologise - my fault for not saying. I don't know, tbh. I'm finding it hard to isolate precisely where the noise is coming from.

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Switched to O2 Standard LLU (from BT) on 3/3/09, Ilford North exchange.

Have you tried removing the side cover whilst it is making the noise, then (not quite) sticking your head in and listening carefully to see if you can identify the source.

Another option, have to tried (gently) rocking the pc whilst it is making the noise to see if the note changes. Or better still try both.

Obvious candidate are the fans and the hdd(s). Fans would most likely be a continous noise, but the HDD may be more of a hunting noise (coming and going).

Probably a fan, power supply or CPU. Of the two I'd guess the power supply is a more likely culprit. To buy a new PSU will cost around £40. e.g. http://www.novatech.co.uk/novatech/specpage.html?HYP...

However you would need to establish if the PSU is the source of the noise and whether your Dell takes standard PSUs (Dell can be a bit odd with their fitments).

Ah, just figured it out - it's the fan.

HDD not particularly noisy, computer making a moderate amount of noise, so I put my hand over the fan vent and whoomph - noise increased to deafening (OK, slight exaggeration).

I reckon that pretty much confirms it.

Doesn't explain why it's loud at increasingly lower temperatures though.

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Switched to O2 Standard LLU (from BT) on 3/3/09, Ilford North exchange.

In reply to a post by john2007:

Probably a fan, power supply or CPU. Of the two I'd guess the power supply is a more likely culprit. To buy a new PSU will cost around £40. e.g. http://www.novatech.co.uk/novatech/specpage.html?HYP...

Thanks, but I think I've just worked out that it's the fan.

In reply to a post by john2007:

However you would need to establish if the PSU is the source of the noise and whether your Dell takes standard PSUs (Dell can be a bit odd with their fitments).

Tell me about it! They rarely take standard power supply units and charge the earth for their replacement ones - as I know from replacing one on my brother's machine.

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Switched to O2 Standard LLU (from BT) on 3/3/09, Ilford North exchange.

I know this sounds silly, but have you tried turning the PC on its side, or even upside down? I have a PC that makes quite a racket when right way up (one of the PSU fans), but turn it on its side and it's silent as the grave. (And, yes, I have checked that all the fans still rotate.)

I am not young enough to know everything.
Oscar Wilde

In reply to a post by cblymie:

Doesn't explain why it's loud at increasingly lower temperatures though.

Has it moved - so vents have less air around or getting warmer air than before. No cables moved inside to block airflow

Is the CPU doing more work? I have a machine at work (similar age) which gets very noisy when CPU underload

Could be fan bearings on way out - increasing noise or ageing is reducing heat transfer to heat sink/CPU getting hotter

Ken

Only two things are infinite, the universe and human stupidity, and I'm not sure about the former.
Albert Einstein (1879 - 1955)

A heatsink fan is in most cases, simple to replace. Usually, there will be 4 screws in the top which drive into the heatsink and a 3 conductor cable which attaches to the motherboard. You simply need to ensure that any replacement is securely fixed and of course, fitted the right way up.
If you need to use the machine and it get's annoying, a carefully aimed shot of WD40 into the fan hub often works wonders. This is a temporary fix only though.

At higher temperatures, the fan spins faster and it could be that it's breaking out of it's "wobble" by doing so.