Difference between raiding SATA, SATA-II or IDE using RAID 0 ?

I know that IDE drives can be raided, but can SATA drives be raided together? can SATA-II be raided? Is there a speed difference between IDE, SATA and SATA-II raids using raid 0?

There are many SATA controllers which provide RAID features on the market today. Some support SATA-II.

As long as the controler is not on the PCI bus, you will be able to take advantage of the available bandwidth provided by a RAID array. PCI (not to be confused with pci-X or pic-e) controllers limit your bandwidth to 133 mb/s; too little for most arrays.

SATA-II's theoretical bandwidth may provide more throughput, providing the drives are SATA-II and the controller supports the protocol. Several factors are involved when determining what benefits there may be.

What did you have in mind for your configuration?

Just experimenting with ideas atm. Would 4 raided SATA-II drives produce a noticeable difference in speed compared to 4 raided SATA drives? Does the 300 mb/s bandwidth of the SATA-II drives actually make a difference in raid 0? Does the 300 mb/s bandwidth of the SATA-II drives make a difference when used separately?

NO "single harddrive can give out 300mb / sec (IDE / SATA / SATAII) the mechanics of todays harddrive simply can not run that fast SATAII 3g is nothing but marketing hype!

NOW - where SATA II would shine is as you would like in a RAID array as you have more bandwidth to use with multiple devices accessing the BUS.

IDE - 133mb
SATA - 150mb
SATA II - 300mb

So ideally SATAII is most beneficial in a RAID 0 array - but a single SATAII HD in terms of plain speed wont show any real gains over an IDE / SATA drive.

Unless a given drive is capable of saturating an interface, the advantage of a faster interface is minimal in terms of throughput.

In terms of real-world performance, rotational speed and latency are more important than the interface.

Some RAID-optimized drives such as the WD Caviar RD2 series have been optimized for RAID configurations and will provide better reliability and maybe a bit more performance than a "vanilla" 7200RPM drive.

Mr.Guvernment said:

NO "single harddrive can give out 300mb / sec (IDE / SATA / SATAII) the mechanics of todays harddrive simply can not run that fast SATAII 3g is nothing but marketing hype!

NOW - where SATA II would shine is as you would like in a RAID array as you have more bandwidth to use with multiple devices accessing the BUS.

IDE - 133mb
SATA - 150mb
SATA II - 300mb

So ideally SATAII is most beneficial in a RAID 0 array - but a single SATAII HD in terms of plain speed wont show any real gains over an IDE / SATA drive.

Click to expand...

Essentially true, Mr.Guvernment, but keep in mind that the interface in question is between the drive and the controller, so as long as an individual drive can't saturate the interface, an interface with higher bandwidth provides no advantage.

The CONTROLLER interface, on the other hand, can have a dramatic influcence on trhoughput. As mentioned earlier, using a pci bus limits this bandwidth to 133 mb/s, while pci-x can see upward of around 256 mb/s and pci-e 8x (like the new megaraid cards) can see up to 500 mb/s. Motherboard-integrated soutions are often the best choice here in terms of value, efficiency and bandwidth.

Mr.Guvernment said:

NO "single harddrive can give out 300mb / sec (IDE / SATA / SATAII) the mechanics of todays harddrive simply can not run that fast SATAII 3g is nothing but marketing hype!

NOW - where SATA II would shine is as you would like in a RAID array as you have more bandwidth to use with multiple devices accessing the BUS.

IDE - 133mb
SATA - 150mb
SATA II - 300mb

So ideally SATAII is most beneficial in a RAID 0 array - but a single SATAII HD in terms of plain speed wont show any real gains over an IDE / SATA drive.

Click to expand...

The SATA-300 300mb/s is a limit per drive cable - not per RAID array. The RAID array's maximum bandwidth is only limited by the bus that the controller sits on (PCI, PCIe, southbridge, etc).

The reason SATA-300 speed exists is because SATA-II brings more features to the table - in particular port multipliers. BTW SATA-300 (speed specification) and SATA-II (features specification) are two entirely different things. Port multipliers are essentially like USB hubs (or ethernet switches) that allow a maximum of 16 connections (one to the host controller which leaves 15 for drives or devices). So if you've got 4 or or more drives on one controller you're going to want 300MB/s. At least.

But the RAID we're talking about here is one drive per controller channel, so it's not an issue.

You will not notice a difference between SATA and SATA-II devices due to the interface speed.

edit: oops hafa beat me to it.

hafa said:

...and pci-e 8x (like the new megaraid cards) can see up to 500 mb/s.

Click to expand...

There are guys bursting at 800MB/s off the new Areca ARC-1220 PCIe 8x 8port SATAII controller.

I can do ~400MB/s off my ICH7R southbridge controller.

hafa, you say motherboard integrated solutions are the best in terms of cost and efficiency. Are there any PCI-X or PCI-E RAID controllers for SATA drives that are better than integrated motherboard solutions? Just wondering, because maybe they might be cheaper, who knows.

PcI-X controllers are fairly affordable, but you'll only be able to use one if your motherboard has the interface. pCI-X is usually only found on server or high-end workstation motherboards such as those from Tyan.

8x pci-e controllers are currently very expensive, starting around $600. You would also need a motherboard with an available pci-e 8x slot to handle it. As with PCI-X, this interface is usually only found on high-end server and workstation motherboards.

If you really wish to avail of the benefits of a RAID array, you'll be best off getting a motherboard with an integrated solution.

Don't forget there is a difference between an "onboard" controller and a "southbridge" controller (or whatever you want to call the two).

An "onboard" controller still resides on the PCI bus (even 'tho it is soldered onto the motherboard), and suffers the same limitations as a PCI card.

A "southbridge" controller has no PCI limitations.

So to expand on what hafa said, you're best off getting a motherboard with RAID supported by the southbridge, not an "onboard" Promise, Sil, or ITE chip.

edit: Alomost all 8x controllers will work in a 4x open ended slot (you can always dremel the end off) or just get an SLI board, and use the second 16x physical slot.

I was looking at doing a raid array in the near future also...

I was wondering how you can tell if the SATA controller isa southbridge or a PCI interface if it is onboard.

My current rig (only running 1 drive ATM) is a MSI k8t800 neo2 but was looking into upgrading to the an8 abit board... The abit baord has the sata2 controller and I would like to take advantage of having 2 sata drives...

Is there a list some where of controlelr type and integration? Thanks

If the RAID controller is listed as being made by intel or nV then it's on the southbridge.

All nF4 boards support southbridge RAID.

And it tells you here:


intel southbridges ending with an "R" support RAID (ie: ICH6R does, ICH6 does not).

edit: Another example (Asus P5WD2)

Thanks JCLW that cleared up a lot of confusion for me. I need to know the max amount of drives that would work efficiently using a southbridge controller. If the southbridge controller only supports a bandwidth of 150 mb/s and you have 4 drives each outputting 60 mb/s, then you're bottlenecked. So I guess my question is, will the bandwidth of a southbridge controller be able to handle 4 hard drives? You'd think the manufacturers would have thought of this before building the board, but I always like to make sure. Google searches give me nothing. I'm not actually worried about the bandwidth of the southbridge, because I know that can handle it.

Also, I'm pretty sure that you can plug IDE drives into a SATA raid controller right?

CrazyBauxite said:

Thanks JCLW that cleared up a lot of confusion for me. I need to know the max amount of drives that would work efficiently using a southbridge controller. If the southbridge controller only supports a bandwidth of 150 mb/s and you have 4 drives each outputting 60 mb/s, then you're bottlenecked. So I guess my question is, will the bandwidth of a southbridge controller be able to handle 4 hard drives? You'd think the manufacturers would have thought of this before building the board, but I always like to make sure. Google searches give me nothing. I'm not actually worried about the bandwidth of the southbridge, because I know that can handle it.

Also, I'm pretty sure that you can plug IDE drives into a SATA raid controller right?

Click to expand...

Different southbridges have different links to the northbridge. Current nV solutions use the hypertransport bus, so the actual speed depends on if you're overclocking, and by how much. Even at stock speeds, it is way faster then any number of drives you are going to put on it (1.6GB/s IIRC). Intel and ATi basically use a PCIe interface to link them. Intel uses four PCIe lanes (I would suspect the ATi chipset does too) giving a max of 2GB/s. Intel calls their PCIe 4x interface the Direct Media Interface.

So as a direct answer to your question if you use drives with an STR of around 65MB/s you would theoretically need at least 24 to saturate a hypertransport bus, and at least 30 to saturate the intel DMI bus.

edit: Remember that all your other southbridge, PCI, and some PCIe devices (but not the graphics card) have to use this bandwidth as well - but they typically don't use that much (ie: 10mb/s for ethernet, etc)

There has been a bit of of confusion around interface names as well. You're comparing PATA and SATA drives, which are both IDE devices. Most current southbridges contain one or two PATA controllers (two devices each) and four SATA controllers (one device each). But they will only allow you to build arrays using the same interface type (and typically only SATA these days). So to use your PATA drive in a RAID array you'll have to pick up one of those little PATA<->SATA adapters.

JCLW you should rename yourself to "Encyclopedia"

JCLW said:

...So to use your PATA drive in a RAID array you'll have to pick up one of those little PATA<->SATA adapters.

Click to expand...

Actually, the RAID controller on the Nforce4 chipset has a feature called "cross-controller RAID" (see page 7 of the afore linked publication) which allows both PATA and SATA drives to be used in a single RAID array.

thanks for the clarification - i had though the 300mb was for the entire SATAII bus.

hafa said:

Actually, the RAID controller on the Nforce4 chipset has a feature called "cross-controller RAID" (see page 7 of the afore linked publication) which allows both PATA and SATA drives to be used in a single RAID array.

Click to expand...

That's neat. I never knew that before.