Is this a new system, or an old one which you just got, or is it a system which you
have been using which suddenly started giving this message?

Have you recently made changes in the BIOS Setup, or have you changed hardware such
as a fan?

Open the case and see if the CPU fan is spinning at full speed.  Also check that the
Power Supply fan and case fan are spinning at full speed.

If you have changed the CPU fan, make sure it has  3-pin connector and that you have
plugged it into the CPUFan motherboard connector.

See if the BIOS has a PSFAN Detect setting....if it does and the Power Supply fan is
not connected to that connector on the motherboard, disable it.

If you haven't just installed or removed any hardware, fans are where I would look
first.