Why not set it up on a staic? A server should be on a static. If you have a cable modem/router/switch thingy check its configuration, likey it will allow you to set up a range for dhcp. Put your servers static ip outside of the range but still in the same subnet.
In your routers config: dhcp range 192.168.0.50-192.168.0.200 (dhcp will assign 150 ip's)
Then the static ip for your server could be 192.168.0.25
This way dhcp never assigns an ip address to another machine for your static ip.
Clear as mud?