Airport Extreme! Broadcom! Oh my!

So, if you don’t care about wireless data connections and or OS X & XP you should ignore this post. I recently did a little 802.11n upgrade to my aging Core Duo Macbook Pro and I bought an “official” Apple 802.11n Airport Card that has 2 antenna wire inputs. It’s chipset is the Broadcom BCM4328. My Apple System Profiler polls this as Broadcom BCM43xx 1.0 (5.10.38.9) and in Windows XP it clearly shows up as the BCM4328. Now, shouldn’t this be all good? Well sort of, there have been some problems.

Under OS X 802.11n (ie Airport Extreme) works like gang busters over the Time Capsule but it seems my 802.11g performance has taken a huge hit. And under XP SP3 both my g/n performance has degraded. So what’s the deal? Well it seems I should’ve gone with an older version of this chipset.

Apparently the BCM94321MC aka the Dell 1500 Part Number NJ449 was the original version, which worked well for people under Tiger. There obviously are other options, but the key here was the 4321 chipset as opposed to the newer 4328 chipset. So what’s the issue? I don’t know. I imagine the XP drivers aren’t fully up to date. And I also imagine 802.11n MIMO works better with 3 antennas which is why the newer Core 2 Duo machines come with the 3 antenna input Atheros wireless cards. Can I add a third antenna wire and put in the Atheros? I don’t know. Should I sell the one I installed and try the $30 Dell 1500 NJ449? I would say yes.

Another issue that has developed is that with around 15% battery the wireless card will go dormant and not startup again without a reboot. Nice. Whatever, I suppose I cannot complain too much. It mostly works.