Asus P5WD2-E Onboard RAID

[jhg]

Do any motherboards provide "real" onboard RAID, or are they all
the hybrid "host-raid" variety?

At one time I bought an Adaptec 1420SA, but found that I could not
use it because it actually increased the frequency with which I had
to rebuild my Windows system. Since, with hybrid RAID, some of the
RAID functionality occurs on the host CPU, a Windows hang/crash
in the wrong place can actually corrupt the disks. Combine that with
the low quality of the Adaptec drivers and it was a recipe for disaster.

Now I want to build a robust SOHO network server/workstation, and
am considering the Asus P5WD2-E Premium coupled with a 3ware
9650 (this combination is on 3ware's compatibility list). I notice
that the P5WD2-E comes with an onboard Marvell RAID subsystem,
but I assume this is the hybrid variety.

I'd be interested in hearing other people's opinions on the subject
of onboard RAID and "true hardware" vs hybrid RAID in general.

 

[MerlinRML]

The Marvell solution is almost certainly a "hybrid" solution and not a true hardware solution.

The problems with the Marvell solution stem more from the fact that it is integrated into your motherboard rather than the problem of it being a hybrid solution. Onboard solutions usually are not very portable, so in the event of a motherboard failure you have to find a motherboard with the same Marvell chip to recover your data. Your RAID array will not just work with any controller you have.

As to whether or not a true hardware solution is better than a hybrid solution is better than software is a complicated answer. Some people swear by hardware solutions, others swear by software.

Hardware RAID can be good if the onboard processor is powerful enough to handle all of your RAID calculations fast enough and keep your disks spinning at their maximum speed. If you get an older controller that is a true hardware processor, and it can't keep up with your disks, how good is that solution really? Also, these cards tend to be quite expensive since you're paying for a dedicated processor. However, these cards mean that your system CPU will have very little to do with the RAID portion, and it will be as available as possible for the user to run. These cards give you dedicated ports for your disks, so you need to buy the appropriate sized card that you need.

Software RAID is very good for portability. You can usually move the disks between systems quite easily, as long as the OS is relatively similar. The downside to this is that your RAID is tied to your OS, and OS problems can result in problems with your data. It also means that your system CPU is doing all of the RAID work. With this solution, you're also limited to the number of disk ports on your motherboard.

Hybrid solutions (a separate card, not onboard) have the ports of hardware RAID, a lower cost, separation from the OS, but they offload all RAID calculations to the system CPU and have the portability of hardware RAID.

I'm sure I've forgotten some details for each solution, but that should give you a start. I'm sure others will chime in to correct me.