NetXen NX 2031 Cards Support No More Than 128 GB of RAM on a Machine (1009386)
NetXen NX2031 cards have a 128 GB limitation on a single machine. This limitation applies to any unm_nic driver version 3.4.350 or higher and occurs because of an underlying NetXen hardware limitation that restricts high DMA.
No workaround is currenlty suggested in terms of using more than 128 GB of RAM on a single machine. However, be aware of this RAM limitation and plan accordingly.
Note that NetXen NX3031 cards do not have this RAM limitation.