right, ill get down to business.
We got a new cable modem/router today, and i have most of the computers in the house connected.
My mac usually feeds internet to my desktop, so i can game my heart out on winXP :3
Well, new modem, and now it is not receiving any packets except the DHCP packs.
IP address is correct between the two computers, just internet sharing is bonk.

OS X 10.5 (Rolled back specifically FOR this setup..)
Windows XP SP 2 on a custom rig.
Nforce4 Ethernet controller, Asus a8n-SLI motherboard.

Of course, trusty AlBook G4 fw800.

Help much appreciated! (No, seriously!)