Quote Originally Posted by Serra View Post
Why do people actually buy hardware add-on cards for RAID-0? Why on earth do others advocate it?
I agree exactly with the reasons you have for the rant. But there are three reasons why someone (me for instance) would do exactly that...

The first is motherboard incompatabilities with certain disks. The particular bugbear I have in mind is the P5K Premium board, one that is still a killer except for the well-known problems with RAID and certain Samsung/WD disks, that are still not certainly fixed in later hardware/BIOS revisions for the board.

The second is the (related) ability to take the card + attached disk arrays and simply slot it into a brand new mainboard without having to worry about whether the Southbridge will read the disk arrays correctly. It likely will, between Intel ICH versions, but then what if you decide to switch to a SLI mainboard with an nForce chipset? Having a RAID card insulates you from that potential problem in upgrading, so it (and working disks/installation) can carry through many builds giving good value for the money spent.

The more expensive the card the better the future options too, you may not want or need RAID5 today, but a mix of RAID0 or RAID1 may do nicely, and then you have the power if you do wish to upgrade later and you aren't limited by the onboard Southbridge capabilities.

The third is the fact that if you are using SSDs or similar solutions, the Intel ICH has a bug that caps throughput and IIRC sometimes causes boot-up issues. Using an offboard hardware controller avoids the bandwidth cap even if for all other intents and purposes it operates no differently from the Southbridge RAID. Anyone with or intending to play with SSDs will therefore need an offboard controller even for RAID0 to make full use of the silly money they've spent. (Yeah, speaking as a 2x i-RAM owner...)

I think you also have to throw in the question of reliability too. The P5K Premium debacle shows that mainboards (perhaps from some manufacturers rather than others) are not terribly reliable and prone to manufacturing problems and design flaws, but also lack of commitment to fix bugs in "non-essential" areas of the BIOS or hardware, such as onboard RAID, which is basically added-on value to the board's main function. I don't know if there are any comparative reviews of the RMA rate or user satisfaction between RAID cards and mobos, but anecdotally on this forum you generally hear people swearing BY their Arecas and AT their Asuses...

The bottom line for this argument, it seems to me, is that RAID card manufacturers make a profit on their ability to make good hardware, and they compete intensively in a specialised market for this function only, so they have an incentive to get it right. Viz the recent Areca firmware fix for the X38 chipset problems with their cards, a little late but certainly welcome for their users. Mainboard manufacturers are just bundling an Intel add-on to their product, so it is not their PRIME focus of business and (as has been shown) their concern for its fitness has been dubious at best. Why are nVidia chipsets STILL destroying data on SATA drives? They can get away with that because people buy the chipset for SLI and know they can work around it. The specialised RAID hardware companies would die in months if they released a product like that.

So despite your unarguable technical objections, I respectfully submit there can still be very good reasons for preferring a RAID card over an onboard solution, in certain situations, however dumb the processing being done.