I'm typing from a lappie and i see two fan rpms:
When you opened HWiNFO you may have seen a popup saying that it detected and an Embedded Controller and that reading it may cause some slowdowns. If you disable it, you won't get the rpm readings. of course if your laptop doesn't have the EC, then you won't get them either.
Sometimes if under no load, I won't see the GPU fan, just the CPU fan
Then, if i load Furmark, the GPU actually has something to do and HWiNFO pops up the rpm