Hello,

I have the AppleBCM5751 kext working, however sometimes my machine freezes during boot. The only way to get around it is to reboot, disable nic in the bios, boot into osx, reboot, enable nic in bios, and then it boots into osx working.

When it freezes during boot verbose mode shows:

AppleBCM5751Ethernet: 1 1659 setPowerLevels - returning early, have a 5721. onoff=, fpcidevice=

Any ideas would be appreciated!

Corbo

I have the same issue, it freezes if I enable NIC in BIOS..if I disable I can load up OSX but without network which I'm trying to get to work.

I am having the same issue as well, havent figured out a fix yet

Well, first of all the AppleBCM5751.kext is not from Apple at all, despite the name. It's a hack from Nisa-IT that pretends to be a driver for the BCM5751 chip, but in reality it's for some other Broadcom chip. The hack allows it to load, but that only begins to address the actual process of driving the hardware.

You're getting the "power levels - returning early" error because the driver, quite simply, doesn't really work for the 5751 chip. Anything that "appears" to be working is completely coincidental and unrelated to the actual workings of the chip.

What chip do you actually have on your network adapter? That's like, er... um... sort of important. If it really is a BCM5751 then you can stop now fooling around with this non-functional kext. No amount of tweaking or fiddling with the plist or anything else will make it work.

I actually have a BCM5751. So are you saying that I should say screw it to the on-board and buy another pci network card? I was looking at getting this if i need it, a realtek 8139 chip PCI network card, http://www.newegg.com/Product/Product.aspx...N82E16833360017

The solution:
1. move the kext from the extensions folder to /var/root/
2. add this line "kextload /var/root/AppleBCM5751Ethernet.kext" to /etc/rc just before "exit 0"
3. sudo rm /System/Library/Extensions.*
4. reboot

It always works when loaded manually.

noob friendly guide on how to do that please

In a terminal type (or cut and paste) these commands:

sudo su -
cd /System/Library/Extensions
mv AppleBCM5751Ethernet.kext /var/root/
rm /System/Library/Extensions.*

Then edit the rc file:

nano /etc/rc

and paste this line
kextload /var/root/AppleBCM5751Ethernet.kext
at the end of the file, just before the last line.

Reboot and it won't freeze during boot. The setPowerLevels error shows up but does no harm.