No huge impact. With your current setup, DHCP servers can register/update DNS records for their clients. However, individual systems (DHCP clients) can do this without the need for help from a DHCP server, and they tend to update their DNS record when their IP assignment changes by default. You can refer to this link for details: https://learn.microsoft.com/en-us/troubleshoot/windows-server/networking/configure-dns-dynamic-updates-windows-server-2003