Hello. You won't be able to accomplish the desired 48GB using the existing DIMMS. This is due to the restriction imposed by UDIMMs, which have a system maximum of 24GB. In order to exceed 24GB you would have to replace the UDIMMS with RDIMMs, which have a max capacity of 192GB. You could upgrade to 6X8GB RDIMMs (part #PK4TR) to achieve the 48GB .   Let me know whether this works for you. 
Hi , I need info on how to upgrade the RAM on my T320.  Config is:  Xeon E5 1410 @ 2.8GHZ single processor Currently has 16GB of Ram 4x4GB modules (UDIMM) I would like to get 2x16GB and bring it up to 48GB combining the already 16GB on it plus 32GB I would buy. what's the best combination to get this done? Thanx 
Poweredege T320 memory upgrade help