AHCI

下周一的8.0-BETA2会包含这个。CAM/AHCI是按照CAM框架重写的AHCI驱动（之前是ata(4)），提供了包括NCQ等硬件特性的支持，并改善了对SATA光驱的支持。与OpenBSD的实现不同，FreeBSD实现通过扩展CAM框架使其直接对ATA设备提供支持。

It seems that a recent ThinkAdvantage update will cause FreeBSD boot manager to have some problem (A “Drive 0” will appear as fifth option, and all other options would not work except a beep). It is possible to recover from this situation by using FreeBSD LiveFS disc (for amd64 platform):

Start from CD-ROM;
Choose “Fixit” and “CD-ROM”;
Now you get the command line prompt;
Mount your hdd to /mnt/;
mv /boot /boot.old && ln -s /mnt2/boot /boot
mv /usr /usr.old && ln -s /mnt2/usr /usr
“boot0cfg -B /dev/ad4” (Note: your SATA controller should be in AHCI mode, otherwise it should be ad0)
Then you will be able to use boot0cfg to configure the boot partition. Reboot system then everything will go well.