Xp Slowness on Server

Age old question I guess. But having a problem when XP Pro is connected to a windows 2000 server and joined. The machine is slow and sometimes stops responding. I have read all the MKB Articles and uninstalled SP1 and set my nics to 10 half in advanced, No antivirus, new nics, blew away computer and user accounts and defragged. but when the machine logs on and to itself, works fine. I have tweaked, troubleshot to no end.I have 4 types of computers on 3 differant networks. differant locations, differant ip schemes. all updates, drivers and …….Help