You can use the kernel module or Ndiswrapper with the M$ driver but not both.
The broadcom chipset is supported in Slackware 12.0 '/lib/modules/184.108.40.206-smp/kernel/drivers/net/wireless/bcm43xx/bcm43xx.ko'.
You could do a 'lspci -vv' to confirm the device. You can see if the modprobe will load the device module. Then do a 'ifconfig -a' to see if it indeed is shown. If it does then just do a 'netconfig' to setup.
53. Card: Broadcom BCM94306MP built-in HP Pavilion ze4560us laptop
Chipset: Broadcom 94306
pciid: 14e4:4320 (rev 02)
Driver: Use driver for Dell Truemobile 1300
Other: Gentoo 2.6.4-r1, NdisWrapper 0.8/0.9 manual compile/install (ebuild does not work). Works fine except dmesg reports “ndiswrapper (add_Driver:1539): Cannot add duplicate driver” Consistent 3.1MB/s thruput, peak at 3.7MB/s. No dropoff in thruput , no instability.
You should be using the Dell driver for Ndiswrapper.
If you indeed got the device active before with ndiswrapper then you should setup a static IP to confirm.
I would setup a static IP first, do as root from cli;
~#ifconfig -a #get recognized devices
~#ifconfig eth0 192.168.1.10 #set to a available IP
~#route add default gw 192.168.1.1 #set to your gateway
~#route -n #show the route table
~#ifconfig eth0 up #should be up already
~#ping 192.168.1.1 #ping your gateway
~#ping 220.127.116.11 #google.com IP
~#ping google.com #test DNS, if fail then
Once you have a static IP working then if you need to use DHCP then run 'netconfig' again or edit the '/etc/rc.d/rc.inet1.conf'. You can restart init with '/etc/rc.d/rc.inet1 restart' from the cli as root.