As you have mentioned that your computer is on for almost 24/7, this might be the cause of overheating. There are few troubleshooting steps that I would suggest.
Please follow the steps mentioned bellow.
1. Releasing flee Power.
Shut down the computer, disconnect the battery and ac adapter, press and hold the power button for 10 to 12 seconds and connect the battery and ac adapter and check.
2. Cleaning the Vents:
-- Check the vents on the computer to see if they are covered with dust thereby not allowing heat and air to pass through.
-- Turn off the System.
-- Unplug the AC Adapter.
-- Remove the Battery, for instructions on how to remove the battery see the Service Manual.
-- Use Compressed Air to blow the dust out of the vents.
3. Update the BIOS:
An out of date BIOS can cause heat issues by an outdated temperature table for the system.
Visit the Dell Drivers and Downloads website to get the update BIOS to your computer.
Please click the link provided below to get the drivers.
--Enter the service tag, and choose the operating system and download the latest BIOS version.
4. Hardware Diagnostics Check:
-- Shut down the computer.
-- Disconnect all the peripherals from the computer. (If it is a desktop, only the monitor, keyboard, mouse and the power cable should be connected. In case it is a laptop only the ac adaptor).
-- Restart the computer and keep tapping F12.
-- It takes you to the One Time Boot Menu.
-- Select Diagnostics and press Enter.
If the test fails capture the error code and get back to us, I would let you know the next course of action.
I would also request you to mention the System Model.
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