Onboard vs PCIe RAID cards?

[Norcross]

I am going to start building my own NAS system (I like to tinker) and I was wondering what (if any) the difference was between using the onboard RAID plugs (such as those on this board) or getting a dedicated RAID card?

 

[Brandon]

These days, nothing really, they both use the PCI-Express bus, so you won't really see speed diffs. Unless you pay an arm and a leg for a good server-type card, it's still software RAID, so it's the exact same thing built into your motherboard.

in the long run, it will save you money, and a port to just use the built in. Depending on the NAS, you might just use it's software RAID as well, which makes the whole arguement Null.

 

[jdabbs]

One disadvantage of using onboard components is the sourcing of replacement parts 1-2 years after the initial purchase. I did a quick check on Pricegrabber for a motherboard I purchased less than a year ago and couldn't find anything. I'd imagine chances would be better if I were looking for a RAID card.

 

[Norcross]

I figured I'd stick with a well known (Asus most likely) if I went the on-board route. Still up in the air for now

 

[zx10guy]

Depending on the add on RAID controller card, there can be significant differences. The onboard controllers used on your typical motherboard does not include a coprocessor nor has its own cache memory. These can be significant differences depending on your RAID setup and the I/O profile of your disk usage....especially if you use parity based RAID schemes. Also, some implementations of onboard RAID controllers don't do well when the RAID volume is in degraded mode. Lastly, if you decide to upgrade your motherboard, you might be in a situation where the new motherboard has a RAID controller which is not compatible with the RAID volume you created with the old motherboard using a different RAID controller. Having a card based controller allows you to migrate the entire array seemlessly with the only issue being drivers for the OS you intend on using.

 

[Norcross]

thanks! the migration issue sealed the deal. card it is.