intel x79 officially support 2 sata 3 port
and most of x79 board support 2 sata3 port and 4 sata2 port..

but ECS X79R-AX Black Extreme board..
http://www.anandtech.com/show/5360/ecs-x...-extreme-review
http://www.techpowerup.com/reviews/ECS/X79R-AX/
http://www.legitreviews.com/ecs-enables-...otherboard_1833
support 6(2 sata3 + 4 sata3 SAS port) sata3 with x79 and another 6 sata3 with legacy sata chip...

ECS, how thay unloak x79 sata3 and sas feature?
is it bios feature?
of custom circuit design make this diffrence??

attached file is bios of this board.. and it is not contain any UEFI SATA driver
it contain sata orom only.
is this orom make diffrence in sata port??

SAS isn't applicable here. You must have a separate SAS controller card/chip (LSI, Intel, 3ware, HP, etc). The systems you speak of are SATA controllers, and not SAS HBA's. Since i cant decipher you usage of bracket and plus sign usage i can provide this information. Most board have either all SATA3 (6gb) ports, or a mix of SATA2 (3gb) and SATA3 (6gb). If your disk drive is an SSD or would be bottlenecked by its speed being greater that 3gb, then use the SATA3 port. Since most magnetic storage is no where near 3gb, save your SATA3 (6gb) ports for your SSD's.

http://www.lowjax.com -- LowJax blog

This topic is very old, however I even registered in win-raid to share some info that may be interesting for other x79 owners.
The message above that SAS is not applicable is just not correct: I actually own ECS x79r-ax and actually use it with a SAS drive (SEAGATE ST3300555SS) connecting it via passive SAS<=>SATA_power+SATA_data adapter and a standard sata cable to the Motherboard. CPU is Xeon E5-2667, doesn't matter I think.

SAS is disabled in BIOS of this motherboard by default, but after enabling it - 4 SAS ports works mostly fine: SAS drive can be used as a boot device, works stable for several years in win10 and linux.
The actual read speed is only 90MB/s but it may be just a disk limitation, mine is old. The average random read of 4k blocks in the first 1G of a drive is ~3.5ms according to linux tool

# ioping -s 4k -S 1G -R /dev/sdb 
 
--- /dev/sdb (block device 279.4 GiB) ioping statistics ---
859 requests completed in 2.98 s, 3.36 MiB read, 288 iops, 1.13 MiB/s
generated 860 requests in 3.00 s, 3.36 MiB, 286 iops, 1.12 MiB/s
min/avg/max/mdev = 181.4 us / 3.47 ms / 7.71 ms / 1.09 ms
 
 

So this motherboards SAS controller is suitable at least for home use.

However I'm not sure how it is enabled via BIOS or some wiring in motherboard. It appears in device listing as PCI VID:PID 8086:1d69 (rev 05) Subsystem: 8086:1d69 "Serial Attached SCSI controller: Intel Corporation C604/X79 series chipset 4-Port SATA/SAS Storage Control Unit"
If the bios conents may be interesting for modders for other MoBos - attaching full raw programmer readout (02.06.2012 ver 2.14.1219).