I don't know if anyone has done a concise writeup, so here goes.
I purchased a used Dell Mini 9 in May 2010 with the intent to make it a very portable media player. I want 4-8 hours of battery life, 9" screen, output capabilities, expandability, compatibility, and a good level of support, and costing less than a new 32GB iPod Touch. My model was the base 4GB/XP in black with no web cam, Bluetooth, or WWAN hardware.
Subsequent upgrades included a GFDL Super Talent 32GB SSD, 2GB RAM, Better-power 5200Wh battery from MDD, and the focus of this guide, the Broadcom Crystal HD 70012 mini-PCIe card.
I am using the Broadcom Crystal HD 70012 mini-PCIe card in my Mini 9. It is indeed the hardware decoder chip that is compatible with a few software packages, including recent builds of XBMC. It does work, and it works quite well, but there are some caveats.
First is that there's no way to run an internal mini-PCIe wireless card and have the 70012 at the same time. It's one or the other, even on the WWAN models. The WWAN slot is mini-PCIe-to-USB, and doesn't actually go into the PCIe bus directly. If you're fine without, with WWAN, or using an external USB Wifi adapter, go for it. Other hacks may also let you run a USB Wifi card internally.
Installation of the card involves four screws. Two of them are removed on the back cover, while the other pair are those on the Wifi card itself. Remove the screws, then delicately pull the antenna cables off, tucking them away. Insert and screw down the 70012 card, then replace the cover.
Now for software:
Linux support is there, is good, but you absolutely have to know what you're doing. I spent 25-30 hours trying to get it to work in Lucid Lynx (10.04) and Jaunty Jackalope (9.04) versions of Ubuntu, with no success, even after consulting some of the guys in the XBMC-linux IRC channel. I am going to try restoring to the Dell Ubuntu image, because the AppleTV Linux/XBMC/Broadcom guide uses Hardy Heron (8.04) Ubuntu, so that's a known quantity.
I have tried once again to get Ubuntu working, but the performance is not what it should be, despite working with some of the project contributors. I believe that it is the ideal operating system for using the Mini 9 as a somewhat dedicated media player, but it's possible that the GMA 950 graphics card support is causing issues.
Windows XP works quickly and simply. It's as simple as installing Windows, updating the Dell drivers, installing the Broadcom drivers, then downloading a very recent build of XBMC (not from their site). My only gripe is that, at least on my Mini 9, when I reboot, I must reinstall the Broadcom drivers to get it to work again. To get around this hassle, I've just resorted to putting the Mini 9 to sleep instead. Upon waking, the drivers are still active.
My experience with it in XP have been very good. I can play full 24-30FPS 1080P movies in XBMC at sub-%50 CPU usage. This is impossible to do without the card. 720P and lower resolution videos also play very, very smoothly, and use even less CPU. The Broadcom card does get quite warm, but that's to be expected.
I did successfully install and set up a Windows 7 environment, and while it did work well, I found that the CPU usage was notably higher. If you are planning on using the Mini 9 for more than just a media player, Windows 7 is probably your best choice.
I can't comment yet on battery life, but I am hoping that it is at least as good as without it. I have seen some testing results that say the card really comes into its own playing 720P and 1080P content, with relation to battery life. That is to say that the improvements in battery life increase as the workload increases. Simply put, the Broadcom does the work better, smoother, faster, and with less power drain the more difficult the task.
The card is only used by a few applications, like newer builds of XBMC. The other software packages on the Broadcom driver page, like KMPlayer, GOM Player, and Media Player Classic also have Broadcom optimizations. (
http://www.broadcom.com/support/crystal_hd/ )
YouTube uses flash, and to the best of my knowledge the latest Beta versions of Flash 10 will utilize the Crystal HD card.
The current download of XBMC from xbmc.org does NOT support the Crystal HD driver, though a future build will. I'm using a build from
http://sshcs.com/xbmc/ and more specifically the OpenGL version, in XP, as I write this, playing a 720P video super smoothly.