Processor Fan Not Detected - How to verify new fan operation via software?

Apparently this is a Dell model with a proprietary CPU fan.  On these models you will always get the Fan Failure notice at power on and have to Press F1.  The only way to get around this is to replace the fan with a Dell proprietary CPU fan.

This is part of the Power On Self Test and the problem is the BIOS is not "seeing" the required signal from the fan, that a Dell proprietary fan provides.  There is no software to get around this as it's part of the built in hardware tests.

If you do a forum search you will find the need for a Dell proprietary fan is well documented.

Thank you, fireberd, for the quick response.

I did, in fact, replace the fan with a Dell proprietary CPU fan.  I no longer get the Fan Failure notice at power on.  At least, I no longer see the notice during startup.  If it is there, it is too fast to see.  The software approach is just my inquiring to see, if I can "see" the signal from the fan, that a Dell proprietary fan provides.  This would tell me that the fan is running.  

Again, it depends on the particular model PC.  Many do not have any provisions (hardware) to enable the fan monitoring (and CPU temp).  Some newer ones can be monitored. I have a Dimension E510 and I can't monitor CPU temp or fan speed.  I have a self built PC with an Intel motherboard and the only software I've found that will show the CPU cooling fan speed is the "Intel Desktop Utilities" monitoring program that came with the motherboard.  I've tried others such as "Speed Fan" and it doesn't show the CPU fan speed.

I did, in fact, replace the fan with a Dell proprietary CPU fan.

May we ask the model?

Some of the Dells that display the "no fan" error rely on RPM feedback to determine the fan's existence and health. For example, I replaced the worn out stock fan in my 2350 with a Vantec 92mm three-wire unit and all is well.

The new fan is operating.

You really do not need software to detect the function of the fan.  Method 1:  Place a damp hand in front of the vent.  If air is blowing, your hand will get cold.  Method 2:  hod a candle near the vent.  The flame will flicker.  Method 3:  Listen for the noise of the fan.  If the CPU is overheating, you will get a warning message about the fan as you have previously,

Yeah, I know.  I just do not feel like crawling under my desk with a flashlight into a dark cramped corner with a candle and a wet hand.  I just wanted the software above board easy way out. 

The Dimension 4500, from what I remember is one of the older Dell's that do not have fan monitoring capability.  I don't even think you can monitor the CPU temperature.  

The 4550, a similar model, boasts thermostatic fan speed control ... somewhere, probably in the BIOS, the temperature and fan speed are monitored and the real-time values stored.