Hello Dan,
Welcome to HUB for your participation.
Coming to your query regarding the SFP+ module if can be attached directly through the NICs card for servers enabled with SFP+ feature or not?
I hope yes can be achieved if we use SFP+ direct-attach passive copper cable (XGM2-2sf option card required). This contains 1,3,5 and 10 meter distance length.
Moreover the XGM2-2sf ports are 10-gb SFP+ ports and do not support 1-Gb optics.
For further reference please refer to the below link:
http://www.extremenetworks.com/wp-content/uploads/2014/02/120675-00_Rev_04_ExtremeXOS_Hardware_and_S...
Please let us know if this helps you for your requirements.