TL;DR: CPU fan has failed to respond correctly, fans are spinning close to 100% and claims the temperature is at 99-100 degrees celsius immediately on startup, neither fully cleaning and de-dusting the inside of the PC nor updating BIOS has worked.

Full:

I have an Alienware Aurora R9 which I bought in late 2019. It’s been running fine up until two days ago. On startup I received an error message:

Dell SupportAssist has detected a failing component on your system that requires immediate attention. Go to http://supportassist.dell.com/ and enter the issue description below:

Service Tag: [not sure I should post this here]

Error Code: 2000-0511

Validation Code: [also not sure I should post this here]

Fan - The (CPU FAN) fan failed to respond correctly.

I got the option to just resume booting up the computer, but when I did, the Top Fan and Front Fan were running at close to 100% speed, and both claimed the temperature was 100 degrees celsius. (by checking the Alienware Command Center app)

I left the computer turned off for several hours (8+) and turned off the heating in the office, so the computer was fully cooled down when I next rebooted it. Still the same error message, and the instant the computer booted up the temperature was registered between 99-100 degrees, and the fans were spinning at close to 100%.

I followed the Dell support link from the error screen. It told me to clean the fan and remove any dust from inside the case, and to update my BIOS.

I opened the case and gave it a dusting with a can of compressed air, and I opened the CPU case to thoroughly cleanse the inside and the fan on both sides.

I tried again, still the same error message, no luck. I updated my BIOS from 10.0.23 to 10.0.25, but that still doesn’t seem to have any effect.

It’s been two days of rebooting, cooling down and cleaning out the computer case, but nothing seems to work. I’ve been able to use the computer for several hours with the fans spinning at max, the temperature never goes beyond 100 degrees, but I don’t know if it’s a sensor misreading it or if my CPU really will overheat eventually. Any suggestions?

EDIT: It also feels like most of my programs and games are really slow to load properly, though my task manager and resource monitor never shows CPU or memory usage above 60% even with several programs open.