[CentOS] Slow network

Hi,

I have problem with a Centos 5.3 computer. The networking is very
slow. The networking card is a RealTek 1GigE. 

I plugged an Ubuntu laptop on the same cable and port with an Intel
GigE, and it's about 8 to 10 times faster. So the problem is likely to
be with the CentOS config.

Any suggestion on how to track down the problem with speed.

I have checked the packets with wireshark, no problem.

Here's my ethtool eth0 output:

        Advertised auto-negotiation: Yes
        Speed: 1000Mb/s
        Duplex: Full

Here's ifconfig eth0

eth0      Link encap:Ethernet  HWaddr 00:06:7B:00:14:16  
          inet addr:192.168.2.103  Bcast:192.168.2.255  Mask:255.255.255.0
          inet6 addr: fe80::206:7bff:fe00:1416/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:3139398 errors:0 dropped:0 overruns:0 frame:0
          TX packets:2890605 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:4048643591 (3.7 GiB)  TX bytes:257250846 (245.3 MiB)

Any suggestion?


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Thanks