I am trying to install a PCI LAN card on my GA-P35-S3G motherboard running Windows XP. Once fitted LAN card is detected by the system and I am able to install drivers for it. I can see the network icon in the system tray and also in the network connections. BUT even after connecting the LAN cable it shows a RED X in the network icon saying the cable is unplugged. Also, there are no indicator lights blinking at the back of the LAN card. I have done the following steps to try resolve the problem but unsuccessful.
1) Checked the LAN cable and is ok because when it is connected to the onboard LAN card it works i.e. network icon shows connected at 100Mbps
2) Tried 3 different LAN cards Realtek, 3Com and D-Link. These LAN cards are working on other machines.
3) Tried fitting on all the PCI slots. There is no problem with PCI slots because my modem and voice boards are working on the same PCI slots.
4) Formatted the HDD and installed a fresh Windows XP.
5) Disabled the onboard LAN from CMOS
6) Updated the BIOS from F2 to F5 downloaded from Gigabyte website

Please help me fix this problem....