The laptop recently began making a very loud grinding/rattling noise, which appeared to be coming from the cooling fan. The noise has now stopped completely, and the fan no longer operates. Each time the laptop is switched on, it displays the following BIOS message: System Fan (90B) Error There is no fan noise or airflow at startup, although the laptop otherwise boots into Windows and appears to function normally. I am conscious that continued use could lead to overheating, so I have stopped using it until it can be repaired. Could you please provide an indication of the likely cost to: Diagnose the fault. Replace the cooling fan (if required). Renew the thermal paste as part of the repair. Advise on your expected turnaround time. The laptop is approximately three years old and has otherwise been completely reliable, so I am hoping it is a straightforward fan replacement. I look forward to hearing from you. Kind regards,