When does it beep? It's either in the BIOS, or some monitoring program loading up. Either way it should be possible to disable it.
I have some experience with Dells. It's not exactly an enthusist board. They're designed to come out of the box, use it, buy another. I don't think you're going to get rid of the error.
But can the old CPU fan be mounted as a case fan... and put a 5 pin molex fan on the CPU? The motherboard wouldn't know the difference since it's hooked up to it's original fan.
I kind of broke the fan... it's not that big of a deal though. I just have to press F1 every boot.
People are stupid; given proper motivation, almost anyone will believe almost anything. Because people are stupid, they will believe a lie because they want to believe it's true, or because they are afraid it might be true. People’s heads are full of knowledge, facts, and beliefs, and most of it is false, yet they think it all true. People are stupid; they can only rarely tell the difference between a lie and the truth, and yet they are confident they can, and so are all the easier to fool.