Hardware or software RAID??

[brashquido]

Ok, I had pretty much set my sights on the GIGABYTE GA-7VRXP as I was planning to setup 2X 30GB IBM ATA-100 7200RPM HDD's in hardware RAID 0 on the RAID controller built into the board. However, I've read on other hardware sights that the IDE RAID controllers built into motherboards such as the GIGABYTE GA-7VRXP, are nothing more than glorified software RAID, and don't offer any performance gains over software RAID. Is this true? If so I may as well get a non RAID board and save myself a bit of cash.

[SpEeDaMiGo]

Actually all these on-board IDE RAID solutions aren't really hardware controllers comparable to some expensive SCSI array contoller for example .. as you said. Regarding their function I'd consider them somewhere in between operating system raid and real hardware raid controllers. On hardware raid controllers all the striping, mirroring and parity bit calculation is performed by their own chip, therefore no CPU load. On so called software IDE RAID controllers (as the one on your board) the striping and mirroring is performed by the CPU hence the name "software" (like software T&L for example on Kyro cards... calculations done by the CPU or whatever ... not completely by the controller itself). Parity calculation isn't performed since it causes a high CPU load. That's why RAID 5 or similar levels aren't available on such cards.
Although you may now think, in this case I won't need any integrated pseudo raid controller, it still offers quite nice advantages over operating system "extreme-software-raid".
First, CPU load with onboard RAID controllers is unnoticeable (striping and such don't need "much" CPU), whereas with OS software raid it's cleary quite higher.
Second, you can boot with on-board controller created arrays, whereas with OS software raid you've got to set it up after OS installation.
Third, you can also use these controller's additional ports as normal ATA ports .... 8 IDE drives as max then together with standard IDE ports.
Fourth, these pseudo-hardware-raids are still quite faster than OS raids (just make sure you set some "good" and appropriate cluster size). It's not just pseudo raid, since there will be a noticeable performance gain, altough don't expect some 100% or even 50% more.
Last but not least, the mainboard version with integrated RAID won't cost you much more than the one without and it's still cheaper than buying a PCI version of such a software RAID controller separately.

Have a look at some reviews of this board, and if they don't report any compatibility issues (like there were on a lot of boards with VIA KT133A and RAID) buy the one with RAID ..... my suggestion. Also check if you can completely disable it in the bios (to free IRQs or INT channels) if you don't need it of course.
I got RAID 0 too .... with some Promise on my Asus A7V133.

Hope this helped a bit; if I'm wrong, please correct me.

By the way, make sure you have some additional cooling for your IBM drives since those get quite hot (together). There were A LOT of broken IBM drives in the past, and I'd say most people didn't cool those babies enough.

[brashquido]

Thanks for the reply SpEeDaMiGo,

I think I will stick to my original plan. It might not be as fast as I can get, but it'll be as fast as I can afford. What would you suggest using for cluster sizes for best stripe performance?

By the way, I know all about the IBM drive problems. I've got 4 of them in my server at the moment, and am replacing them for 3 X 160GB maxtor's which will give me a lot more storage space, and should run a lot cooler. At the moment I have to leave the lid of my case so the drives can "breathe", otherwise I start getting some nasty clunking sounds after about 12 hours.:scared:

[FranchiseJuan]

I have a Epox 8K3A+ with a Highpoint H372 chip on board. I could never really get a difinitive response on what the optimum cluster size should be. When I setup my raid setup, I just set it to the default 64k, but am now thinking if it was really that optimum. I experience quite an increase in sustained writing speeds, but don't quite experience the drive index (in sandra 2002), that I would expect. Should I have setup the raid 0 setup with larger cluster sizes?

Overall I would definately go for a board with Raid then without. The highpoint is, in my opinion a better controller then the promise one..... The raid version of the Epox and the non raid one only differed in price by $12 (here in australia), and to get a PCI card would have cost $100. Well worth the money in my opinion.

[brashquido]

Thanks FranchiseJuan,

I actually found an explaination of the effects of stripe sizing at the link below.

http://www.storagereview.com/guide2000/ref/hdd/perf/raid/concepts/perfStripe.html

[theReal]

I have read another test some time ago (couldn't find it anymore, sorry) that tested performance of a Fasttrak IDE RAID controller. The result was that the optimum stripe size for this controller was 1x or 2x the cluster size of the harddrives - best results were at harddrive cluster sizes of 16 and 32.

Since NTFS limits you to cluster sizes of 4k (you can format with higher cluster sizes, but then you cannot defragment the drives...), I'm using 16k stripe size with my HPT controller because I don't want to be the stripe size to be too small, but not too much bigger as well. I heard from someone else with a HPT controller that 16k was indeed a very fast and good setting.