The system BIOS is 2.0.1, and it appears that a 2.7.0 is available. I have a Dell Server Update Utility (SUU_741_x32_96) DVD issued March, 2014 and found a later SUU published December, 2014 still supports the PowerEdge 2950, so I'm downloading it. The SUUs issued in 2015 seem to have dropped support for the PowerEdge 2950.
Attempts at using the SUU on CentOS 7 1503 64-bit Live KDE DVD fail in a number of ways. The suu utility script bombs out with basic shell errors, and while attempting to use the repository resources directly, the Linux environment seems to have either bogged down and become unusable or has cratered.
Using the CentOS 6.5 i386 Live KDE DVD seems a reasonable next attempt.