Alienware M14x R2 boot up speed slows down drastically after switching to AHCI mode

Hi YC MOOK,

The default setting for SSD for Alienware M14xR2 is RAID. The considerable drop in boot speed is because the SSD drive is no longer being used for caching purposes.

In AHCI configuration the hard drives work independently whereas in RAID mode the hard drives work in collaboration and complement each others functions.

In AHCI mode as the hard drives are no longer associated to each other, so the SSD is no longer being used for caching purposes and hence there is a significant drop in system performance.

You need to change the SATA operation in BIOS to RAID and re-install the operating system and install the IRST driver and configure SSD for acceleration purposes. You may refer to the article Here. 

Note : Please backup the data before re-installing the operating system as it leads to complete data loss.

Hope this helps. Please reply if you have any further questions.

Hi,

To avoid any confusion, I want to clear something out: default SATA mode on the BIOS depends on the configuration of the system, the m14x r2 is offered with 4 different configurations for storage devices, SSD or HDD alone, SSD+mSATA on RAID 0, HDD+mSATA caching SSD and HDD + mSATA boot drive. It's safe to asume, given your explanation, that you have a caching device, in which case the configuration in the BIOS should be RAID, but there is no need to re install the OS if the caching drive is disabled, you only need to do this:

1. Open the start menu.

2. Right-click on "Computer" and select "Manage"

3. Find "Disk Management" under Storage and there should be 4 partitions, the C: drive, the recovery partition, the system reserve and the mSATA device, right click on the mSATA drive and select "Format" and make sure it's set as "unallocated space".

4. Install the Intel Rapid Storage Technology driver if it's not installed yet, here's the link for the download:

M14x r2 Intel Rapid Storage Technology driver (IRST) 

5. Follow the steps in the article shared by Sundeep (How to Enable Caching on mSata SSD for Alienware Laptops?) and start from the part that says "After Windows Reinstall" 

The SATA mode in the BIOS will be changed automatically after you follow these steps, you don't need to change it yourself.

Hi Natalia thank you so much for the very useful info. But I already proceeded to reformat my computer and did a fresh reinstall of windows before I saw your reply. Anyway I still have some doubts regarding the mSata SSD. 1.) What is the different between the enhanced mode and the maximized mode? which one is more commonly used? After I have set the mSata SSD to enhanced mode in future if I want to reformat my computer again must I disable the mSata SSD?

Hi YC MOOK,

The answers to your questions are as follows :

• Enhanced mode uses a method called write-through. In this mode, when data is written to the drive, it is written to both the cache and the hard drive at the same time. This keeps the performance for writes to the slowest writing device which typically is the hard drive.
  Maximized mode uses a system called write-back. In this case, when data is written to the system, it is written to the faster cache first and then back filled to the slower hard drive. This gives the fastest write performance possible but has one big problem. In the event of a power failure or crash, it is possible that data will be corrupted on the hard drive if it has not been fully written. As a result, this mode is not recommended for any form of critical data system.
• Enhanced mode is recommended by default.
• No, you do not need to disable SSD for re-installing windows.

Hope this helps. Please reply if you have any further questions.