EDIT: Version 17.10 has now been released, see the post Dell EMC Server Update Utility SUU 17.10 released.
The latest version of Dell Server Update Utility (Dell SUU) 15.12.00 was released on the 19th December 2015. The Dell SUU is an application used to help patch Dell PowerEdge servers. It will compare currently installed drivers and firmware with those available on the mounted iso file.
Dell now have a product support page for the Server Update Utility which can be found on the link below.
The Dell Server Update Utility SUU 15.12.00 release can be downloaded below, and is now a whopping 17.5GB in size for the 32bit version and a slightly smaller 12.5GB for the 64bit version.
To make sure it is compatible with your Dell PowerEdge server I recommend you go to their technical support website, enter your Server’s TAG, and then look in the System Management section for the latest version for your server.