Software RAID vs. Hardware RAID

[Coherence]

So, it seems the two onboard SATA RAID controllers on my mobo can't each take a separate drive for use in a RAID setup. Because of this, since most onboard RAID controllers (even SATA ones) are still tied into the IDE/PCI bus, and can only read/write to one drive at a time, you lose any speed advantage to striping (RAID0). I think benchmarks by Anandtech have demonstrated this previously in various articles (the whole "RAID0-isn't-worth-it-despite-theoretical-speeds" debate, though things may be different today).

It was recommended to me today by an MCSE associate that the RAID emulation available with dynamic disks in Windows XP (via the Disk Management control) will actually perform better, in this case, because the two drives can be installed on any channel(s) you want (and if they are on separate SATA or IDE channels, you'll get the full benefit of a striped array because both can be read/written to simultaneously, unlike when they are on the same IDE channel).

Anyone have any practical experience with this? To be honest, I don't think the guy who told me about it really had much experience doing it, he just knew it could be done and how to do it. He was talking in a kind of, "If it was me," thing...

 

[elecrzy]

don't even bother with Windows XP's for raid(it's slow). If you want hardware RAID 0, 1, or 0+1, a 20 to 50 dollar card will work better. expect to spend 100+ dollars for a raid 5 card.

 

[Pariah]

Because of this, since most onboard RAID controllers (even SATA ones) are still tied into the IDE/PCI bus, and can only read/write to one drive at a time, you lose any speed advantage to striping (RAID0).

One of those myths that's been passed down through generations as if it were true, but isn't. There will be some loss in performance since if you have 2 drive capable of 60MB/s and they are connected to an ATA100 controller, obviously even theoretically they can't achieve 120MB/s. However, they are not limited to 60MB/s combined either.

RAID emulation available with dynamic disks in Windows XP (via the Disk Management control) will actually perform better, in this case, because the two drives can be installed on any channel(s) you want (and if they are on separate SATA or IDE channels, you'll get the full benefit of a striped array because both can be read/written to simultaneously, unlike when they are on the same IDE channel).

No such thing as emulated RAID. He's likely right, but the additional 20-25MB/s you will pick up will amount to almost no real world performance gain.

Windows RAID 0 is not bootable, so keep that in mind.

If you want hardware RAID 0, 1, or 0+1, a 20 to 50 dollar card will work better.

Bull. The benefits of getting a card, are better portability (windows RAID can only be read by WinXP/NT/2003), and the ability to boot RAID 0 (Windows RAID 1 is bootable). There are no performance, stability, or data integrity benefits of going with a cheap software controller over Windows RAID.

 

[batmanuel]

One advantage of doing RAID in software is that you aren't tied into one particular kind of hardware controller. This can be a huge issue if you are using onboard RAID controllers and you are trying to move drives from a machine with one brand of RAID controller to a new one with another (for example, migrating from an Intel chipset using ICH6R to an nForce chipset using nV RAID). You can always get a controller card if you need the best of both worlds (portability and performace), but a decent one will set you back almost the price of a RAID-enabled motherboard.