I've got an older Precision 650 tower that had one of the CPU/Case fans fail.  I found, what I thought was, an identical replacement on ebay for the original Nidec Beta V fan.  However, once I installed it, I still go the CPU fan failed error, even though the fan was spinning.

Upon further inspection, I noticed that the original part number was M35105-58, while the replacement that I got was M35105-57.  They are both 3-wire.  Is there that much of a difference between the parts that the MB won't detect the fan?  Or am I missing something?

Thanks.

Jason