New Home Server motherboard raid controller VS Controller card.

[Pieter Joubert]

Morning all,

I'm trying to part out a home file server that I will be putting together and at this time I'm stuck with a raid dilemma.

I have a Asus Hero VI that I want to use as my motherboard for the server just because its new and its laying around also I know it able to run raid 5 via the motherboard. As my search for information has done on over the last couple of weeks I have seen many people talk about how bad onboard controllers are and to get a detected card like an LSI or adaptec, but most of the post are 2012 and older.

My question is can any one tell me if the more resent motherboards built in controllers are at the point were I don't have to spend $600 on a card also bypassing the potential of having compatibility problems as some post have described.

Thanks a head of time for any help.

 

[popatim]

What will the server be running?
The problem with motherbd raid 5 is the cpu must perform the parity calculations. If you get a decent cpu and all this is doing is serving files then the cpu raid5 should be 5. If you plan to transcode live streams while writing huge files to the raid; you'll bog right down.

 

[Paperdoc]

There are two major dilemmas / discussions on mobo vs. add-on card for RAID controllers.

1. Future-proofing.
There is NO "Standard" for any RAID. The specifics of how info is written and read on a RAID array are set by the controller and its programming. Thus, IF you try to move a set of HDD's in a RAID array from one controller system to another, there is a good chance it will NOT work. The best chance for success is if your new controller is made by the same company as your old one. In fact, many makers of RAID controller cards (and some makers of mobo controller chips and their BIOS code) promise that they will NOT change their ways of doing things, so that you can rely on being able to buy a replacement (for a failed RAID controller) from them and it will work.

So how do you use that? Well, IF you use the RAID abilities of your mobo, AND if you choose the mobo according to what assurances you can get from the maker of the mobo's HDD controller chip, you may be able to replace a failed mobo with another that uses the same chip maker's products and it will work. I did that successfully. I chose my mobo with this in mind and it did fail after a few years (bad caps). I bought a replacement mobo from a different manufacturer, but still using an HDD controller chip from the same company as the original board. It worked perfectly for my RAID1.

Alternatively, if you are going for an add-on RAID controller card, most of those companies offer the same assurance. Sometimes it is more like: we may change our system in future for new cards, but we promise also to keep making cards using our old system. Either way, what you really need is to choose a card supplier with a long solid reputation so you can have confidence they will be there in 5 or 10 years if you need them.

2. Performance.
ALL mobo-based RAID systems are software-based. The actual controller chip is not the real factor determining performance here. These systems have the RAID programming stored in the BIOS chip. To do the work for RAID processing, the system MUST use the main CPU and RAM, thus diverting resources from main processing work. Thus, this system is bound to be slower than something dedicated.

There are add-on RAID controller cards that are quite low-priced, and that is because they also do NOT do their own work. They, too, use programming code stored on their own BIOS but executed by the main mobo CPU and using mobo RAM, because they do NOT have those resources themselves. The only significant resources they have is the HDD controller chips to handle the HDDs attached to them. These types of cards also are software RAID.

The expensive add-on RAID controller cards carry their own dedicated hardware, as well as software in their BIOS chip. Such cards have their own processor chip, their own RAM and their own HDD controller chips. This is true Hardware RAID. They do ALL the work of running the RAID array themselves, using virtually no mobo resources. Thus they are faster than mobo-based (or cheap add-on card) RAID, because they leave the mobo resources fully available for their tasks. Now, just how much faster is something to consider. You pretty much have to research thorough testing of such systems to find out what performance the three types of RAID can provide. In doing so, you'll find pretty quickly that the answer depends heavily on what type of data processing you are doing, so you will have to asses your own plans and apply that to the research info you find.

Bottom line for your question is: using "the latest" mobo controller chips has almost NO bearing on the relative performance of mobo vs. add-on (expensive) dedicated hardware RAID cards. This is because no mobo contains its own separate processor and RAM resources dedicated to RAID processing. Only the better add-on cards (true Hardware RAID) do that.

Popatim has made an excellent point for you to consider. All the discussion about performance concerns how much of the mobo's processing power is going to be used up in RAID tasks, and thus not available for other "main" tasks. BUT if this machine is ONLY doing the RAID work and acting as a server on your network, that may not matter at all.

 

[Pieter Joubert]

Thanks to you both for the help, popatim the server will be running server 2008 r2 and i also have an 4770K that is OC to 4.4 but runs stock at 3.9. All I'm planing to do with the server at this time is to use it as a backup location for my wife's computer along with my main computer and some storage for the usual stuff music photos doc's software, i don't have anyplace to stream video from it what so ever atm. I do however think i will be running a small SQL data bass of it for a secret server deployment for the house hold. Also i will be using this opportunity to learn Server os and what i can do with it.