COMPAQ SG3000 The PC is making a very loud whirring sound. I have googled this and it appears that it may be the hard drive or the fan. I have taken the back off the pc and it is full with dust!!!! Also.. this PC has been running really slowly for months! Can you help?

First of all use a vacuum and a soft brush to take away all the dust from the inside. Take care not to remove any connections. After this use a blowgun (if available) to clean the dust from difficult places. The power supply and the CPU blower tend to have more dust that you can imagine. Alternative you can use air under pressure but you have to wait some minutes after the cleaning for the humidity to calm, otherwise you may destroy the pc. Start up the pc and check for results.

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Stelios
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Hi,

As you have the back panel off, clean the dust using a hair dryer or a vacuum cleaner. Locate the source of the noise, there are multiple fans inside the chassis. If the noise is from some fan, use hair dryer to clean it up, clean the heat sink on the processor using the dryer.

If the noise is from the hard drive, disconnect and reconnect the cable and check again. If it still continues i would recommend you to backup your data. As in future it might crash due to physical disk damages.

Note: Turn off the PC before troubleshooting.

Regards,
Shrey