Here's the intel link and excerpt from the configuration. I initially installed Win7 but none of the onboard devices worked, including the LAN port, after the first bootup and reboot. I then discovered Win7 wasn't supported with the configuration.
https://www.dell.com/support/manuals...ee2&lang=en-us
1x Processor Skylake Xeon E3-1225v5
1x 8 GB DIMM (ECC)
1x 1 TB Enterprise hard drive
1x DVD RW drive
Supported Operating systems
Microsoft Windows Server 2012
Microsoft Windows Server 2012 R2
Microsoft Windows Server 2008 R2 (test only)
Microsoft Windows Server 2016
RHEL 7.2
Ubuntu 14.04, 16.04