Gigabyte GA-X58A-UD7 Motherboard Review Update: RAID 0 Performance
by Mark W. Hibben
When Virtual is Good
Hard disks remain among the slowest components of the personal computer with many disk operations still measurable in seconds, and thus hard disk performance can directly impact the user's subjective impression of the speed of a personal computer. RAID (Redundant Array of Inexpensive Disks) systems can alleviate the speed bottleneck by using multiple disks to write data in parallel, the so-called RAID Level 0 system. When the RAID 0 system is implemented in a hardware disk controller, the write and read speeds can approach a factor of 2X compared to single disks. This was part of the motivation behind the selection of the Gigabyte GA-X58A-UD7 motherboard for a recent product review, since it featured a Marvel 9128 6 Gb/s SATA 3 controller. The controller supplies only two SATA 3 ports, but supports configuring these as a two disk RAID 0 system. At the time of the review, only one Western Digital VelociRaptor WD6000HLHX SATA 3 drive was available. Since then, we've been able to obtain a second drive and have configured a 1.2 TB RAID 0 system using Windows 7 x64 as before. Both the performance results of the RAID system and the ease of installation of Windows 7 came as pleasant surprises.
The WD VelociRaptor WD6000HLHX is a 2.5 inch hard drive that comes mounted in a heat sink/carrier that affords mounting in a standard 3.5 inch drive slot.
Don't let the heat sink fool you, the drive barely gets warm to the touch, despite its 10000 RPM rotation speed. This latest Raptor also supports the latest SATA-3 6 Gb/s interface and has an unformatted capacity of 600 GB. We connected a pair of these to the Marvel 9128 controlled SATA ports and were off to the bios to configure the Marvel controller for RAID 0 duty. The Marvel set-up utility was actually quite easy to use and if you're familiar with making BIOS settings changes, you'll breeze through this in a few minutes. Even if you're not familiar with your BIOS, following the clear instructions in the Gigabyte motherboard manual will take you through the process step by step.
Step 1: Configure the SATA ports to be AHCI rather than IDE compatible. SATA RAID always requires the newer AHCI protocol. In general, whether using single disks or RAID systems, selecting AHCI should be the user's default for any SATA-3 drives. Unfortunately, most BIOS defaults still use the IDE setting, so this usually has to be changed manually.
Step 2: Enter the Marvel RAID utility and select the drives to be used for the RAID system. Yes, I know there're only two drives, but the utility still expects you to select them. It's all very DOS-primitive, but not difficult.
Step 3: Inform the utility that you want to create a “virtual disk” from the selected drives, using the RAID type of your choice: RAID 0 for parallel disk use (increases speed), also known as striping, or RAID 1 which duplicates the data on both disks for data security, also known as mirroring. As drives have become extremely reliable, mirroring is only used for servers and other mission critical applications. I’ve never bothered with it.
If all is well, you'll see something like the following screen:
The beauty of hardware RAID is that once it's configured, the operating system never knows the difference between a virtual disk and a single physical disk, as long as it has a driver for the RAID system. Alas, in olden (pre-Vista) times, coaxing the OS onto the RAID system was an interesting exploration of the chicken and egg paradox in which the user had to proffer a driver (on a diskette no less) to the OS installer at just the right moment. Nothing like that was required for the Win 7 installation. The installer recognized the virtual disk with no fuss or additional required driver, and partitioned and formatted the drive as required. Installation proceeded normally and the system started up without a hitch. I must say, Windows 7 really works well.
RAID 0 Performance
The VelociRaptor RAID system achieved sequential read and write speed improvements of better than 50% over the single drive performance, which was already excellent, demonstrating > 100 MB/s class performance. More importantly, this low-cost RAID system demonstrates sequential read and write speeds comparable to solid state drives with much greater capacity and lower cost. This low cost RAID system even beat the performance of a much more expensive Ultra 320 SCSI RAID system using an Adaptec controller and Seagate Cheetah 15000 RPM drives. Shown below are the PassMark Disk Mark results for the Gigabyte motherboard, identified as “Corei7SingleDrive” or “Corei7RAID”, and the Ultra 320 SCSI RAID system identified as “V64Q9550OCFull”. The Corei7 system uses the Gigabyte GA-X58A-UD7 board and a Core i7 930 processor running at the stock speed of 2.8 GHz. The Ultra 320 system uses the Asus P5E WS Pro motherboard, a Core 2 Quad 9550 processor overclocked to 3.4 GHz, an Adaptec 2230 SLP SCSI RAID controller, and Seagate 15K.5 Ultra 320 SCSI drives (model number ST3146855LW). The Gigabyte board sports Win 7 x64, while the Asus uses Vista x64.
The sequential read and write tests write or read a very large test file to the disk as a continuous stream of data. The files are deliberately large enough to force actual disk writing or reading rather than merely being written to the drive 32 MB cache, a much faster operation.
In the random seek test, a very large file is created, then a random seek is performed within the file.
A 16 KB block is read or rewritten, then the test seeks another random part of the file. This test is highly dependent on seek time, which is a function of disk rotation speed. Not surprisingly, this was the one area where the 15 K RPM Cheetahs outperformed the ‘Raptors, in a ratio that very nearly matched the simple ratio of the disk rotation speeds.
The sequential read and write results for the ‘Raptor RAID 0 system are comparable to a high quality solid state drive at a fraction of the cost and many times the capacity. Considering that the Marvell RAID controller comes with the Gigabyte motherboard, it’s an even better deal.