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Question: Can 12 sata drives via a sas backplane  with sff-8087 mini-sas out be attached to this card?
Document: Running with Ubuntu 12.04 - works great out of the box. This card will support &#62; 2TB drives. Using with 2 x 3TB drives - works perfectly.
Added to a WHS build with 13 drives. This card controls five drives, so the other connectors on the card will go to another backplane when I add it to the server box. I had an increase in file transfers across my network from 38mb/s to 67mb/s, the average transfer speed around 53mb/s. No complaints, happy with the price and performance.
I'm using this on a FreeNAS system, on an old DFI nForce4 AMD board. Running ZFS so I can't speak to the onboard RAID, but it works just fine to expose four Barracudas and an SSD, with no signs of saturating even when all are running full speed. (I ran a set on bare-disk aggregate benchmarks before setting up zfs).You will need a splitter cable to connect to sata drives.
ZFS scrubs (showing off mostly read performance) now top 450MB/sec, even with the relatively slow, low power drives. Couldn't be happier with the performance, really. Install was a plug and play affair on Fedora 14, no fuss at all. It's also worth noting that my (accidental) downmoding of the card to x4 had no other ill effects, and it worked fine, as it should.
(more on that)Overall, it is a pretty expensive card for just mirroring drives. I would buy it if I had a computer that didn't support SATA3 controller or if I had a 4T hard drive (which I do and hence why I am using the card) that the motherboard doesn't recognize in RAID configurations. But lack of RAID 5 makes this a fairly limited card given the number of physical drives that I can connect to it.The software for this card is just terrible.
Sure there are cheaper cards, but after you buy them all, trying to find one that will work, you'll spend more money than if you just buy this one to start with. Goofy raid controller interface, reminds me of highpoint, but it gets the job done. To get the PCIe 3.0 version you will spend 3 times as much, and I doubt its worth it. This card is a perfect for moderate (low?) price and high performance applications of up to 8 drives.
It took 5 days to initialize. I pulled a drive and replaced it with another. Rebuilding... 7 days. I did another test. Fresh RAID1 with the same 2 drives that successfully initialized before. Rebuilt the array and started initialization. Started copying data. The card would make the drives available and format them but during the copy, it would say one drive was bad. Rebuild the same array with both drives and let the RAID1 initialize completely before copying and no problems.
Bought 3 for a norco esxi/oi/napp-it home setup. mobo is a p8b ws. passthrough worked with no issues on all 3. oi sees all drives on all cardsOnly minor annoyance I had was updating the firmware. oi/napp-it work best with IT firmware (because IT firmware disables raid mode on the card). These come with IR firmware. You cant simply overwrite IR firmware with IT firmware. You have to erase the IR firmware first, then install the IT firmware.
I can't really rate this one highly enough. While playing with ZFS on Linux, all the flaws in my storage subsystem (8x2TB Seagate LP drives in a port multiplier chassis, all going back to an i7-920 fileserver) really were shown up. Read speeds barely cracking 50MB/sec were the norm. Tests with md didn't show much better, so it was obviously time for an improved storage adapter setup.Migrating from the port multipliers to this card got double the speed, even with relatively slow drives.
As a bonus, optical drives work too. Highly recommended.
Answer: I have 33 drives attached with two backplanes.  no problems thusfar.