Slow access to W2K Server

I'm experiencing slow access to my W2K server (PDC). We have 40 workstations all running W2K Pro and 3 servers. Two of them are small servers used only for file storage purposes and for PDC we have a DELL server, with Xeon Proc, 2gb RAM, lots of disk, etc. and only one NIC. All machines access the other 'old' servers in a failry speed but for the PDC it's very slow, even copying 10megs can take more than 2 minutes. All NIC's in the network are hard-coded 100/full
All clientes are using DHCP. The PDC is the DHCP server and DNS server. It's also connected via a VPN to another town where we have our firewall and proxy.
I wonder what could be wrong that would be causing such poor performance
Below is the ipconfig of the PDC server

Windows 2000 IP Configuratio

Host Name . . . . . . . . . . . . : sv-sipnet-0
Primary DNS Suffix . . . . . . . : dummy.com.b
Node Type . . . . . . . . . . . . : Hybri
IP Routing Enabled. . . . . . . . : N
WINS Proxy Enabled. . . . . . . . : N
DNS Suffix Search List. . . . . . : dummy.com.b
com.b

Ethernet adapter Intel 82544GC Based Network Connection - Onboard

Connection-specific DNS Suffix . : dummy.com.b
Description . . . . . . . . . . . : Intel(R) PRO/1000 XT Network Connec
io
Physical Address. . . . . . . . . : 00-0B-DB-94-92-8
DHCP Enabled. . . . . . . . . . . : N
IP Address. . . . . . . . . . . . : 10.55.51.
Subnet Mask . . . . . . . . . . . : 255.255.255.
Default Gateway . . . . . . . . . : 10.55.51.
DNS Servers . . . . . . . . . . . : 10.55.51.
Primary WINS Server . . . . . . . : 10.55.10.
NetBIOS over Tcpip. . . . . . . . : Disable

*******************************************
And below is the IPCONFIG of a typical workstation
Configuração de IP do Windows 200

Nome do host . . . . . . . . . . . : richar
Sufixo DNS primário. . . . . . . . : dummy.com.b
Tipo de nó . . . . . . . . . . . . : HÃ*brid
Roteamento de IP ativado . . . . . : Nã
Proxy WINS ativado . . . . . . . . : Nã
Lista de pesquisa de sufixo DNS. . : dummy.com.b
com.b

Ethernet adaptador Conexão de rede local

Sufixo DNS especÃ*fico de conexão . : dummy.com.b
Descrição. . . . . . . . . . . . . : VIA VT6105 Rhine III Fast Etherne
Adapte
Endereço fÃ*sico. . . . . . . . . . : 00-E0-7D-EE-61-5
DHCP ativado . . . . . . . . . . . : Si
Configuração automática ativada. . : Si
Endereço IP. . . . . . . . . . . . : 10.55.51.4
Máscara de sub-rede. . . . . . . . : 255.255.255.
Gateway padrão . . . . . . . . . . : 10.55.51.
Servidor DHCP. . . . . . . . . . . : 10.55.51.
Servidores DNS . . . . . . . . . . : 10.55.51.
10.55.10.
Concessão obtida . . . . . . . . . : sexta-feira, 27 de fevereiro de 20
4 09:02:3
Concessão vence em . . . . . . . . : sexta-feira, 27 de fevereiro de 20
4 21:02:3
************************************************** ****************

Note the IP address 10.55.10.2 is at the other side of the VPN (a 2mb radio link). Could it be the cause of the problem

Any help would be appreciated

Richar




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Unlock this Gigabit adapter link speed?

How would it help since all workstations and other servers are running in 100/full ?