Nexus 7k - M / F Series I/O Module , Fabricpath Requirement

[tckoon]

Hi,

I am lost and can't tell what is actual different between M-series and F-series I/O module.

Under what condition we shall choose to use  M-series or F-series 

Another question regarding fabricpath.

Refer to below url link , it stated we must have F-series I/O module installed to support fabricpath.

But M3 do support fabricpath. 

https://www.cisco.com/en/US/docs/switches/datacenter/sw/5_x/nx-os/fabricpath/configuration/guide/fp_interfaces.html

"" Note""You must have an F Series module installed in the Cisco Nexus 7000 Series device to run FabricPath.

https://www.cisco.com/c/en/us/products/switches/nexus-7000-series-switches/models-comparison.html#~tab-m-series