Dell OptiPlex 980 (Early 2010) - Manual (Page 17)

NOTE: This option is only available when Dynamic DNS Update is enabled.
Defines the interval at which the firmware DDNS Update client will send periodic updates. It should be set according to
corporate DNS scavenging policy. Units are minutes. A value of 0 disables periodic update. The value set should be equal or
greater than 20 minutes. The default value for this property is 24 hours - 1440 minutes.
6. TTL
1. Under the Intel ME Network Name Settings, select TTL and press Enter.
2. Type the desired time (in seconds) and press Enter.