How to activate AHCI for fast PC startup (in 5 seconds)

Normally, a PC with Windows 10 takes some time to boot which can be 20 or 30 seconds up to even one minute depending on the computer used and the system configuration. The boot time can in fact be very long on an older or very cheap PC, which still uses a traditional hard disk and which has many programs set to start automatically. As we know, both these problems can be easily solved: you can in fact replace the hard disk with a faster SSD and it is easy, in Windows 10, to disable programs in automatic start.
In addition to these basic steps, with Windows it is also possible to activate a quick start feature of the PC that significantly reduces the startup time, loading the desktop in 4 or 5 seconds, with an immediate power on like that of a smartphone or tablet .
To obtain this incredible advantage, it is only necessary to activate, in addition to the quick start option, the AHCI mode (Advanced Host Controller Interface), which is a different Serial ATA or SATA connection technology between the motherboard and the disk.

What is quick start "> what happens when the PC turns on. Basically, the operating system kernel is loaded with some drivers, programs, libraries and other types of data which are then read from the disk, end up in memory and they are executed or processed in some way by the processor. On an SSD this process is already fast enough and after about twenty seconds the desktop should appear. This period of time can be reduced even more by activating the quick start function of Windows 10, that was already present in Windows 8. However, even if this feature is activated, there are some requirements to be able to take full and true advantage of it and to get the PC to turn on in a few seconds.

How do you activate quick start?

I had already written a quick start guide in the article on the quick start, restart and shutdown options of Windows 10.
Very briefly, it is a boot that takes advantage of the hibernation function of the computer, saving the state of the PC in memory which will then be reloaded from the memory itself. To activate quick start, you need to open the energy saving options of Windows 10 from the Control Panel, going to Power Options and then click on the left side, on Specify power button behavior . Here you will find the option to activate Quick Start .
NOTE: This option may be unavailable because Windows 10 detects a lack of requirements to activate it. You can still try to activate Quick Start by clicking on the link at the top of the window " Change settings currently not available " (be careful though, the PC may have problems restarting if it encounters problems with this configuration, then read the guide carefully above and proceed only if you are then able to use the recovery console to return to the previous configuration).

How to know if Windows loads with quick start?

If Windows 10 starts in quick start mode, when you turn on your PC, the desktop or login screen will open immediately after a few seconds. If instead you see the startup animation, the one where those points turn in a circle, then we are with normal startup.
Keep in mind that quick start doesn't work when you restart your computer, but only after you turn it off and then on again. In other words, quick start can only occur after you shut down your computer. Quick Start does not activate after an update or after installing or removing a driver.

Computer requirements to get quick start

Conditions vary from system to system, in some cases quick start works normally, but in most cases some requirements are required:
1) Windows must be started via UEFI . If you have installed Windows 10 in BIOS mode, you can switch from BIOS to UEFI by converting the disk to GPT without having to reinstall everything.
2) The latest SATA / NVMe driver from the motherboard manufacturer (depending on the version of Windows 10 installed) must be installed because the generic Windows drivers are not compatible. You can check this by pressing the right mouse button on the Start button and then opening the device manager . Under the storage controllers section, if you see something like " Standard SATA AHCI Controller " it means that you are using generic drivers, if you read Intel SATA Controller or similar, instead, then the driver is installed.
3) Quick Start must be enabled in Power Options, as seen above, and must be enabled by default. It should also not be viewed as an unavailable option.
4) You need to use a fast storage device such as an SSD or NVMe drive . The quick start might also work with a hard drive, but it wouldn't be fast at all since the hard drive is too slow.
5) That AHCI mode is enabled in the computer's UEFI BIOS .
This is the most important and decisive part to get a quick start up of the computer and let's dedicate a separate paragraph to it.

How to activate AHCI on PC

AHCI is a type of SATA connection that makes it faster to read data from an SSD drive, with the immediate effect of having a computer boot from a few seconds.
Activating AHCI is, theoretically, very easy: you only need to access the UEFI settings and look for options related to SATA or disk configuration, usually under the section dedicated to peripherals. When you find an option that contains AHCI among the choices, then it can be activated by changing from IDE SATA or RAID to AHCI .
If the activation fails, then the PC no longer starts showing a blue screen error that says something like Boot Device not accessible . In this case, do not panic, just reset the option that deactivates AHCI and the PC will start up again normally.
To activate AHCI more cleanly and resolve the error, you can proceed as follows:
Turn on your PC normally and load the desktop. Open the command prompt as administrator (look for cmd in the Start menu) and then give the following command:
bcdedit / set safeboot minimal
Restart your computer and enter the UEFI BIOS to activate AHCI.
Windows 10 will now start in safe mode, without problems (in theory)
Once the desktop has loaded, give the following command to remove Safe Mode and then reboot again:
bcdedit / deletevalue safeboot
If the quick start does not activate or there are errors
The previous steps should be sufficient to speed up the startup of the computer, but if it did not work, the only way is to look for the most updated drivers from the motherboard manufacturer's website and look for specialized solutions in the specialized forums.
Keep in mind that some configurations may have an Intel Optane SATA controller which in itself, if activated, is a fast access mode to the SSD disk.
While the advantage of AHCI and quick start is very clear, I still recommend that you do not go beyond changing the standard options if you are not experienced in correcting computer startup problems. You don't have to panic if your PC doesn't boot anymore because we know it depends on the unsupported AHCI configuration, but it's always better to avoid riskier steps and random changes. In some cases, only a reinstallation of Windows 10 from scratch can allow you to enable quick start and support AHCI mode