WinXP Peer-to-Peer

I'm putting together a 2 PC's Peer-to-Peer Win XP NT, I cant get the 2 to communicate, I can't PING from one to the other, I'm running TCP/IP, I'm using 204.204.7.0 255.255.255.0. out of desperation I also installed NETBUI and still can't ping, Im using CAT3 cable 4 the moment, one of the systems is a AMD 1700XP 256RAM and AMD 700 192RAM, both NICS are 10/100 runing at 10,small hub,win XP the two of them.
I ran the Win XP network set up program from win XP, but all i can see in my network places is the computer Im at, one is MD1 and the other one is MD2, ok on md1 i see md1 only, and on md2 i see md2 only, what im i missing? Please advice!
Help
Thanks
MDL