Dynamic control for fan speed during system boot and reboot in hot and cold environments

1. A method for dynamically controlling fan speed of a computing system during boot and reboot, the method comprising:

receiving an ambient temperature from a sensor by a controller; and

controlling fan speed for one or more fans dynamically based upon the ambient temperature using a dynamic algorithm during boot and reboot of the computing system, wherein the dynamic algorithm comprises a function for the fan speed of the one or more fans based upon the ambient temperature, wherein the function is a third-order polynomial function represented by Boot PWM (%)=A*AMBIENT 3 +B*AMBIENT 2 +C*AMBIENT+D, wherein Boot PWM(%) represents duty cycle of PWM fans in percentage, AMBIENT represents the ambient temperature measured by the sensor, and A, B, C, and D are constants.

2. The method of claim 1 , wherein the sensor comprises a temperature sensor, a relative humidity sensor, a pressure sensor, or a combination.

3. The method of claim 1 , wherein the ambient temperature is in the range of less than −5° C. to greater than 55° C.

4. The method of claim 1 , wherein the controller is a baseboard management controller (BMC).

5. The method of claim 1 , wherein the computing system is a network equipment building system (NEBS) system.

6. The method of claim 1 , wherein the one or more fans comprise pulse-width-modulation (PWM) fans.

7. The method of claim 1 , wherein the function is a third-order polynomial function represented by Boot PWM (%)=A dew *AMBIENT 3 +B dew *AMBIENT 2 +C dew *AMBIENT+D dew if the ambient temperature is lower than a dew point, wherein constants A dew , B dew , C dew , D dew have lower values than constants A, B, C, D to reduce airflow and thus the risk of condensation.

8. A system comprising:

a storage device configured to store instructions;

a processor configured to execute the instructions and cause the processor to:

receive an ambient temperature from a sensor by a controller, and

control fan speed for one or more fans dynamically based upon the ambient temperature using a dynamic algorithm during boot and reboot of the computing system,

wherein the dynamic algorithm comprises a function for the fan speed of the one or more fans based upon the ambient temperature, wherein the function is a third-order polynomial function represented by Boot PWM (%)=A*AMBIENT 3 +B*AMBIENT 2 +C*AMBIENT+D, wherein Boot PWM(%) represents duty cycle of PWM fans in percentage, AMBIENT represents the ambient temperature measured by the sensor, and A, B, C, and D are constants.

9. The system of claim 8 , wherein the sensor comprises a temperature sensor, a relative humidity sensor, a pressure sensor, or a combination.

10. The system of claim 8 , wherein the ambient temperature is in the range of less than −5° C. to greater than 55° C.

11. The system of claim 8 , wherein the controller is a BMC.

12. The computer-readable medium of claim 11 , wherein the function is a third-order polynomial function represented by Boot PWM (%)=A dew *AMBIENT 3 +B dew *AMBIENT 2 +C dew *AMBIENT+D dew if the ambient temperature is lower than a dew point, wherein constants A dew , B dew , C dew , D dew have lower values than constants A, B, C, D to reduce airflow and thus the risk of condensation.

13. The system of claim 8 , wherein the computing system is a NEBS system.

14. The system of claim 8 , wherein the one or more fans comprise PWM fans.

15. A non-transitory computer-readable medium comprising instructions, the instructions, when executed by a computing system, cause the computing system to:

receive an ambient temperature from a sensor by a controller; and

control fan speed for one or more fans dynamically based upon the ambient temperature using a dynamic algorithm during boot and reboot of the computing system,

wherein the dynamic algorithm comprises a function for the fan speed of the one or more fans based upon the ambient temperature, wherein the function is a third-order polynomial function represented by Boot PWM (%)=A*AMBIENT 3 +B*AMBIENT 2 +C*AMBIENT+D, wherein Boot PWM(%) represents duty cycle of PWM fans in percentage, AMBIENT represents the ambient temperature measured by the sensor, and A, B, C, and D are constants.

16. The computer-readable medium of claim 15 , the sensor comprises a temperature sensor, a relative humidity sensor, a pressure sensor, or a combination.

17. The computer-readable medium of claim 15 , wherein the ambient temperature is in the range of less than −5° C. to greater than 55° C.

18. The computer-readable medium of claim 15 , the controller is a BMC.

19. The computer-readable medium of claim 15 , the computing system is a NEBS system.

20. The computer-readable medium of claim 15 , the one or more fans comprise PWM fans.