Depends on the version of HDMI. http://en.wikipedia.org/wiki/HDMI#Versions
Some versions support higher output. Also the HDMI cable needs to be compatible with the required version of HDMI.
The GT 650M supports HDMI 1.4a so can theoretically run higher res, but this depends on the implementation of the manufacturer, i.e. Dell, and also if the notebook has Optimus, it is possible that the onboard GPU may limit the output res on the HDMI port in order to be able to switch GPU's as necessary.