Most computer hard drives work independently. A more advanced option involves setting up a Redundant Array of Independent Disks, or RAID, which turns your separate drives into a team that works together. The broad strokes are the same for any computer, but the details vary by manufacturer. If you have an ASUS motherboard, you'll need to know the quirks of the ASUS RAID setup.
Reasons for RAID
There are two reasons for setting up your hard drives as a RAID array. One is to provide extra data security. Under those configurations, if one drive fails, data is protected because it's on other drives.
And then there's speed. If four drives are reading and writing at about the same speed, it's four times faster. It'll take most of the noticeable lag from a system using conventional hard drives, and a RAID array built from solid-state drives (SSDs) can be breathtakingly quick.
Whatever your reasons, the steps begin by installing two or more disks, depending on which RAID configuration you choose. Then you can turn your attention to the software.
Getting Into Setup
You'll enter the ASUS UEFI BIOS to enable RAID, which simply involves getting into the motherboard's settings. If your computer doesn't have Windows Fast Startup enabled, you can restart it and press the F2 function key to get into settings. If Fast Startup is enabled, you'll take a more roundabout approach. From your desktop, click the "Start" icon and then the "Settings" icon. Select Update and Security, then choose "Recovery" from that menu. In Recovery, choose "Advanced Startup" and then "Restart Now." This takes you to a blue screen where you'll click "Troubleshoot" and then choose "Advanced Options." From the next menu, choose "UEFI Firmware Settings" and finally "Restart." Your computer will reboot, bypass Fast Startup and take you into your setup screen.
ASUS RAID Setup
Once you're into the UEFI settings, you'll see a screen filled with various options. An ASUS BIOS takes you by default into "Easy" mode, where you'll have basic settings to choose from. That doesn't include your RAID options, so you'll need to click "Advanced Settings." For most drives, your next step is to click "SATA Configuration" and hit "Enter," then set the SATA mode to RAID.
Next, go to the Boot settings, choose "CSM" (Compatibility Support Mode) and set Launch CSM to "Disabled." Save your changes and exit the BIOS setup, then follow the same steps as before to go back into the setup screen. This time, you'll find a RAID configuration tool in the Advanced Settings. There isn't an ASUS RAID tool or ASUS RAID controller as such, so you'll be working with an Intel or AMD utility, depending on whose chipset is on your motherboard.
Your RAID Options
At this point, decide how you're going to configure your array. For gamers, RAID 0 won't protect data, but will give blazing-fast read and write times. RAID 1 is slower but gives great data protection. RAID 5 compromises, offering great performance while breaking up backup data across all drives. RAID 10 makes pairs of drives into two or more RAID 1 arrays for data protection, then treats them as a pair of RAID 0 arrays to give you higher performance than you'll get with RAID 5. The downsides are the added cost – you need at least four drives – and the slight but real risk of losing data if both drives in a pair fail. Do your research – there are more choices.
Configuring Drives With AMD's Utility
If your motherboard uses an AMD processor and chipset, you'll see the RaidXpert2 configuration utility when you go back into the BIOS. To set up drives, go into Array Management and then choose "Create Array." Click "Select RAID Level," and choose from RAID 0, 1, 5, 10 or any other options offered. Then click "Select Physical Disks" and set the toggle to "On" for drives included in the array. Click "Apply Changes" to continue.
If your drives are identical – always the best option – you can choose the full size of the individual drives in Array Size, the next option. If they're different, choose the size of the smallest drive. Select the Array Size Unit, usually gigabytes or terabytes, and then choose the read and write policies you want your cache to follow. If you don't know, do a quick internet search. When you're done, choose "Create Array." Save your settings, exit and reboot to use your array or install an OS on it.
Configuring Drives With Intel's Utility
If your system uses an Intel processor and chipset, you'll get Intel's Rapid Storage Technology utility when you reboot. The menu options have slightly different names, and you'll see more of them, but the process is pretty much the same.
Start by selecting Create RAID Volume. You'll give your array a name, then choose the RAID level and physical hard disks to use. For RAID 0, 5 or 10, you'll choose a strip size, which is how it backs up data across disks. Go with defaults, unless your research tells you otherwise. Enter the size of the RAID array in the Capacity settings, and then click "Create Volume." Save your settings, exit and reboot to use your array or install an OS on it.
But Wait, There's More
These choices all apply to standard drives on SATA connectors, those seen on your motherboard. If you want maximum performance, or you're short on conventional drive bays and drive connectors, you can build your RAID array out of SSDs mounted on a PCIe expansion card that goes into one of your computer's card slots.
Configuring these involves additional options you'll need to research. You'll follow the same steps for installing drives and going in to change BIOS settings, but from there many settings will be different.