BroadcomMegaRAID SAS 9460-8i - Storage controller - 8 Channel - SATA/SAS 12Gb/s low profile - 1200 MBps - RAID 0, 1, 5, 6, 10, 50, JBOD, 60 - PCIe 3.1 x 8

Just to clarify the other reviewers, I have been a network systems engineer for over 30 years. RAID (redundant array of independent disks) is a way to add redundancy to multiple hard disks giving you one volume for access that is made up of many disks. The total storage capacity of the RAID volume is based on the type of RAID you choose. I have outlined the most common RAID capacities below because the other reviewers are providing inaccurate information.RAID 0 (Striping) - Total Capacity of all disks. NOTE: you can use different size disks but larger disks will be reduced to the capacity of the smallest disk in the RAID array. There is no fault tolerance with RAID 0RAID 1 (Mirroring) Total capacity of all disks / 2 (i.e. N / 2) Must add drives in pairsRAID 5 (Striping with Parity) - Total capacity of all disks minus one. Note that the same drive size issues exists if you use drives of different capacities as written in RAID 0 comment above. (N -1 * size of smalles drive in array) five 1TB drives would give you the total capacity of 4TB but five 1TB drives and one 500GB drive would yield a total capacity of 2.5TB. In a RAID 5 setup you can increase the array by adding a single drive at a time but must start with a minimum of 3 drives. At any point you can lose any single drive in the array and it will still function properly without data lossRAID 6 - Same as RAID 5 but you can lose 2 drives without suffering data loss. total capacity is (N - 2 * size of smallest drive)RAID 10 - Basically its two RAID 0 sets that are mirrored together (RAID 1+0 get it, RAID 10). So you create two sets of RAID 0 striped volumes and then mirror them usiing RAID 1. capacity is the same as RAID 1 which is (N / 2) but you have to add drives to each array so they must be added in pairs.There are RAID levels 2,3,4,7,50,60 but those are rarely used with the exception of 50 & 60 which are used usually in very large enterprise environments. RAID 50 and 60 are again like RAID 10. 50 = two mirrored RAID 5 arrays and 60 = two mirrored RAID 6 arrays. 5+0 and 6+0.Summary, This card is a good card and works well if you need the performance that it offers. The setup is fairly straight forward if you have setup other cards in your system that have their own BIOS. If your buying this for home use, there are cards that will probably better suit you as this is likely overkill for any home use. If your in a multi user environment of using to build a SAN or NAS for multi-user or high demand access then this is a great card. I would get a battery and enable write-back caching to increase performance even more. My 2 cents. Enjoy!

As I said, it is not as compatible with a PC as it should be. I can't get into bios settings, nor other things. I get a blue screen of death every first boot of the box, but then the second reboot works = weirdness. I got this so I could have a 4 disk, and eventually an 8 disk RAID-5 array for my Windows box. Also, the RAID-5 really isn't RAID-5 but might as well be RAID-1. The point of RAID-5 is that you are supposed to get more usable disk space from mutiple disks than from RAID-1. Well, I don't. I have 4x 2 TB disks and I got a 4 TB usable disk space, not 5 or 6 TB that I should have gotten. Not happy. But I'm stuck with it. This is also a newer card, so I had hoped that it would run a bit cooler. It doesn't. Do I recommend this product? NO.

In RAID 5 you get an error correct array but sacrifice 1/3 your total of the disks combined.In RAID 1 it mirrors the 2 drives so you have complete redundancy but at a high cost (a total drive instead of 1/3 of one).But in all fairness I have 3 controllers running RAID 10 which is striping (spanning) and then another span set backing that up. The advantage is that it is fast and completely redundant. I have had a drive die before on one of the systems I didn’t have a spare configured to just “drop in” where the faulty drive was and rebuild but I was not in any hurry to replace the drive. However I did order a new drive and replaced it.You can add more drives to your RAID 5 array and you will get (total of disks * 2/3) and have redundancy to one failed drive. In other words one drive can fail and your system will keep humming along.As far as the system not booting on the first try you may need to set the RAID controller to “Legacy mode” to get to the controller BIOS.