Try to use the information showed in this post:

 

http://apeteget.blogspot.com/2008/05/dell-poweredge-r300-debian-etch-40.html

 

It's in spanish but have the essencials commands to get debian running.

 

Sorry my poor english i'm spanish.

The best way I find to install debian etch 4r3:

 

1. Install debian without ethernet configuracion (skip this step).

 

 

2. Once you install debian base packages init session with root user.

 

3. Install via aptitude o apt-build: linux-headers-`uname -r` (uname -r to find out your kernel version) , unzip and make:

$ apt-get install linux-headers-`uname -r` unzip make

 

 

 

4. Donwload in other pc broadcom drivers and copy them to a usb pendrive:

 

http://www.broadcom.com/support/ethernet_nic/downloaddrivers.php (Drivers Main page)

 

If you have Netextreme card use tg3 drivers you must download the drivers from this link:

 

http://www.broadcom.com/support/ethernet_nic/driver-sla.php?driver=570x-Linux

 

if you have Netextreme II card use bnx2 drivers you must download the drivers from this link:

 

http://www.broadcom.com/support/ethernet_nic/driver-sla.php?driver=NX2-Linux

 

5. Create a directory in mnt where you will mount your pendrive and mount this:

 

$ mkdir /mnt/usb && mount /dev/sdb1 /mnt/usb

 

6. Copy the file downloaded from broadcom driver's page to /tmp/ dir an unzip them:

 

$ cp /mnt/usb/your_drivers_file.zip /tmp/ && unzip your_drivers_file.zip

 

7. The last operation have created a long directory path. In the last dir must be aq tar.gz file with the source code of the ethernet driver. Copy this file to /usr/src dir and extract it.

 

8. Go to the extracted directory and execute $ make and when finish $ make install.

 

9. Now you have your ethernet running, you can try $ ifconfig eth0 for more info. You must only config your ethernet information in /etc/network/interfaces file.here is a example with static ip:

auto lo
iface lo inet loopback

auto eth0

iface eth0 inet static
address 192.168.0.182
netmask 255.255.255.0
broadcast 192.168.0.255
gateway 192.168.0.1

The next time you reboot you will have your ethernet running.

 

I hope have helped you with that steps.