X-bit labs

Review of MSI 875P Neo-FIS2R Mainboard on i875P Chipset (page 4)

Category: Mainboards

by Ilya Gavrichenkov

[ 06/12/2003 | 01:21 PM ]

RAID in ICH5R

We haven’t yet discussed in our reviews the Serial ATA RAID controller built into the South Bridge of the i875P chipset. Now, we are going to bridge this gap. So, for the integrated RAID to function properly, the following requirements must be met:

• You need the RAID-supporting ICH5R South Bridge. The marking of this chip is Intel FW82801ER;
• The controller must be set to the RAID mode in the BIOS Setup (it can also function in the mode with two independent channels);
• Two Serial ATA HDDs are attached to ICH5R;
• Serial ATA RAID driver called Intel Application Accelerator RAID Edition is installed.

Note: for today, ICH5R only supports Level 0 RAID (stripe), but Intel promises an upgrade, so that it could also support Level 1 RAID (mirror). Moreover, the RAID driver for ICH5 is now available for Windows XP only; the driver for Windows 2000 is going to appear soon.

It’s an easy thing to build up a RAID array. Let’s see how it’s done with MSI 875P Neo-FIS2R. First, we enable the use of Serial ATA channels and say Yes to the option “Configure S-ATA as RAID”:

After that, there appears a special RAID BIOS during boot-up. You can go in and configure the array there. But that’s not necessary as there is an easier way: Intel Application Accelerator RAID Edition allows configuring an array from Windows XP. By the way, you cannot install this driver-utility without enabling the RAID mode in the BIOS: the installation will go abort mumbling something about incompatibility.

After Intel Application Accelerator RAID Edition has been successfully installed, the system installs the RAID driver:

From Intel’s utility you can create and configure a RAID array. The creation is a simple task: just answer a few questions from the driver:

Now that the array is created, the two hard disk drives are recognized by the system as a single drive of a double capacity (if you use two identical drives).

In theory, you can install Windows XP directly onto the RAID array. MSI 875P Neo-FIS2R comes with a floppy carrying an appropriate driver.

Note: when ICH5 works in the non-RAID mode, you won’t need any drivers at all. In this case Windows XP itself finds the Serial ATA controllers and disk drives.

There is one important thing about the driver support of IDE controllers in ICH5. Earlier, Intel offered its standard Application Accelerator for IDE controllers in its chipsets. This Accelerator performed buffering of disk operations, resulting in a certain performance gain for the disk subsystem. But with the launch of i875 and i865 chipsets, Intel Application Accelerator has entered the league of RAID drivers and abandoned IDE controllers support. So, mainboards with ICH5 don’t have disk buffering on the driver level anymore. To put it simpler, office applications that actively use the disk subsystem run slower on i875 and i865 than on previous chipsets as far as disk access time is concerned. We can’t say why Intel gave up writing intelligent IDE drivers for its new chipsets.