If you want to have dual boot on this computer you can't. Because of the iRST ( RAID ) Intel RST is not necessary since you have only one SSD running Windows. RST is used for RAID configurationsSomething wrong about this computer. I think it used has HDD for another purpose like it was on the shelf for another company but it was discontinued and put in the ssdAfter +2 days, I found the solution. I hope it helps somebody elseEdit: I've had this computer for over 3 years. It is a gem. No regrets. I would buy it again.1. Click the Start Button and type cmd2. Right-click the result and select Run as administrator3. Type this command and press ENTER: bcdedit /set {current} safeboot minimal (ALT: bcdedit /set safeboot minimal)4. Restart the computer and enter BIOS Setup5. Change the SATA Operation mode to AHCI from either IDE or RAID6. Save changes and exit Setup and Windows will automatically boot to Safe Mode.7. Right-click the Windows Start Menu once more. Choose Command Prompt (Admin).8. Type this command and press ENTER: bcdedit /deletevalue {current} safeboot (ALT: bcdedit /deletevalue safeboot)9. Reboot once more and Windows will automatically start with AHCI drivers enabled.