Hardware RAID questions

[nywst]

Basically I wanna do hardware RAID, instead of onboard RAID which is software RAID anyway. Questions:

1. Any performance comparison doc between RAID 0 through addon card and onboard? (personal computing of course)

2. In term of performance, which one is better: RAID card on PCI Express or on PCI?

3. How about this card?
http://www.newegg.com/Product/Product.asp?Item=N82E16816115027
Its interface is PCI Express x4. If my PC only has one PCI Express x1 slot available. Will this card work? Will the performance suffer?

4. Any suggestions for addon RAID card? (<$150 is better)

Thanks for any comments.

 

[Pain]

Generally speaking, you have to spend more than $150 to get a true hardware raid controller. If I had to guess, becasue I'm not 100% sure, but if I were to guess that controller you link is also a software controller.

If you look in the storage section of THG, they did a review of several raid controllers back at the end of last year. It may give you some information even though I think they are PCI cards, but it will at least give you something to read about.

 

[bmouring]

1) I've seen comparisons on many different mobo-based RAIDs compared to higher-end cards (some here on THG, some elsewhere). From what I recall, there is a slight performance increase when using hardware RAID usually (there are cases when the mobo RAID is actually faster). In other words, you'd probably better have another reason for going hardware-based RAID. I did it because I needed to dual-boot Windows and Linux from a RAID 0 whish is basically impossible on anything less than a real hardware controller. Other reasons include portability (in both the ability to move the entire array and controller to a new machine and the ability to migrate one RAID configuration to another, e.g. adding a new disk and going from 0 to 5)

2) PCI express. PCI (standard, 32-bit bus at 33MHz) is a shared bus at, at max, can deliver 133 MB/s. Since it's shared, you won't be getting that bandwidth most of the time. My array has 2 74GB raptors and even that rather modest array can get 130+ MB/s to the OS, which would absolutely be throttled by PCI. Get either a PCIe or a PCI-X controller.

3) It's a nice card, but again it's not a true hardware controller. Also, unless your 1x PCIe slot is physically a larger connector, it just won't fit. However, if your mobo is SLI-capable and you have no need to do SLI you can use one of those slots for the card instead.

4) Your best best for true hardware RAID is some stuff from Areca (entry level is the ARC-1210 four-port SATA PCIe x8)

 

[nywst]

Thanks a lot, everyone!

Could you provide the link for comparion doc between onboard and addon RAID? I couldn't find from THG

 

[bmouring]

Here is an older (but still relevant) benchmarking round. Please keep in mind, however, the numbers they have posted for the 9500S are lower than those I have personally found on my system, likely a by-product of them using the controller on a PCI slot (shared with other devices) instead of using it with a proper PCI-X slot. My results for the benchmarks I've run that they cover in the reviews show a slight improvement over the on-board controllers, but never an incredible improvement (except, as noted in the review, 0% CPU use).