SATA - AHCI vs compatibility mode

sameh83

Well-Known Member
#1
I am having much problems with my laptop graphics for a while now ! I currently have my bios setting to compatibility mode and i was wondering ,,,,if i reinstall windows,, what setting should it be on ? And which setting is the recommended one for my Lenovo T-61 running windows 7 32 bit ? And lastly, what is the difference between all the different settings ? and, would switching out of current mode (compatibility) make a difference in graphic resolution ?

Thanks in advance
 


sameh83

Well-Known Member
#2
By the way, i ONLY switched to compatibility after i reset my bios to default settings by accident ! I never knew the original setting !
 


#3
AHCI will give you slightly better performance. You'll need to reinstall the system.
 


Saltgrass

Excellent Member
Microsoft Community Contributor
#4
I must be missing something, what does the SATA mode, which determines how the hard drives are controlled, have to do with graphics? Are you saying the performance is poor and you think improving your hard drive performance will help?
 


#5
SATA mode can not improve the graphics, of course. But of AHCI vs compatibility mode I'd choose AHCI for the performance of the hard drive, not the video card.

1. Currently have my bios setting to compatibility mode and i was wondering ,,,,if i reinstall windows,, what setting should it be on ?

If I was reinstalling the system, I'd try AHCI.


2. And which setting is the recommended one for my Lenovo T-61 running windows 7 32 bit?

I don't know. You current mode is compatibility, was it always this way since you bought your note, have you ever reinstalled your system - no idea.


3. And lastly, what is the difference between all the different settings ? and, would switching out of current mode (compatibility) make a difference in graphic resolution ?

As Saltgrass pointed, a SATA mode won't make a difference in graphics. AHCI will make the hard drive a little faster, but I'm not sure that you won't have to install the ahci driver during the windows installation process.
 


sameh83

Well-Known Member
#6
Clarification,,,,I have did a fresh install a few times since second owning this laptop ! I HAD no idea about the settings, and that's why i asked. Besides, Installing the AHCI driver will be like any other installation,,,,,correct ? If so, i am confident that it will be a simple task ! btw, like i said earlier, i have no idea what the original settings are ! I ran into this problem a few weeks back when i entered BIOS and set the BIOS to default settings by accident !
 


Saltgrass

Excellent Member
Microsoft Community Contributor
#7
Because I have not seen a compatibility setting for a SATA controller, if that is what you mean, could you please be specific about where in the bios the setting is you refer to and what other options you have?

If you are talking about a compatibility setting for your video, which should be in a different area, that might limit the system to a low res operation. But again, knowing the other options would help. I will see if I can find a manual for you system and try to check the bios settings.

Edit -----------
I found this, but I could not find an owner's manual with the bios settings.
 


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sameh83

Well-Known Member
#8
Thanks ,,,i will look in a few for you !
 


sameh83

Well-Known Member
#9
Here are a few screen shots of the BIOS options ! Note: for the HDD there is AHCI and compatibility ONLY (current setting is Compatibility) . Now, for the Display options in BIOS, i am confused as to the correct setting,,,,,i provided 2 screen shots with the options available ! Hope they will help !
 


Attachments

Saltgrass

Excellent Member
Microsoft Community Contributor
#10
I am still a little confused. The SATA options you show as "compatibility" with no other options shown, are not related to the Display options you show in the other attachments.

You have the Thinkpad display shown, so you should be seeing a normal display if you have a driver for the onboard video. If you right click on the desktop and select screen resolution, what resolution are you showing?
 


sameh83

Well-Known Member
#11
Here are a few screen shots of the BIOS options ! Note: for the HDD there is AHCI and compatibility ONLY (current setting is Compatibility) . Now, for the Display options in BIOS, i am confused as to the correct setting,,,,,i provided 2 screen shots with the options available ! Hope they will help !
I never said the four screens provided are related ! I made sure that was clear ! however, all i asked was,,,"what are the correct settings for this type of laptop" ? Please stop confusing yourself !
 


Attachments

#12
True the SATA mode is not a graphics mode... but both SATA and Graphics are sharing the system buss. Anything that lags that buss is going to lag the graphics a bit. AHCI mode has better buffering and seek algorythms that place a lot less load on the PCI and PCIe buss in a computer so they can appear to speed up your graphics a bit. On some older laptops this might be readily apparent.
 


sameh83

Well-Known Member
#13
I have a question,,,,,i am getting ready to switch from compatibility setting to AHCI in BIOS ! However, i have 2 seperate partitions, one with the OS and another with my personals ! When i make the switch,,,,will i still be able to access my D drive (personal) ? or will i need to do a complete format of the entire drive and start over ?
 


#14
I have a question,,,,,i am getting ready to switch from compatibility setting to AHCI in BIOS ! However, i have 2 seperate partitions, one with the OS and another with my personals ! When i make the switch,,,,will i still be able to access my D drive (personal) ? or will i need to do a complete format of the entire drive and start over ?
You'll be able to access both partitions with no problems. You may need to be sure you have the latest AHCI SATA driver available just in case Windows 7 asks for one after you change the BIOS settings.
 


#15
I have a question,,,,,i am getting ready to switch from compatibility setting to AHCI in BIOS ! However, i have 2 seperate partitions, one with the OS and another with my personals ! When i make the switch,,,,will i still be able to access my D drive (personal) ? or will i need to do a complete format of the entire drive and start over ?
Short anser Yes. Once windows discovers what you've done and puts in the correct driver, you'll have full access to the disk drive, just like before. All you're changing is disk access, not disk content.
 


#16
Windows will not put the correct driver alone. You need to edit the registry before you change the bios or it will bsod until you change it back:


  1. Exit all Windows-based programs.
  2. Click Start, type regedit in the Start Search box, and then press ENTER.
  3. If you receive the User Account Control dialog box, click Continue.
  4. Locate and then click one of the following registry subkeys: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Msahci
    HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\IastorV
  5. In the right pane, right-click Start in the Name column, and then click Modify.
  6. In the Value data box, type 0, and then click OK.
  7. On the File menu, click Exit to close Registry Editor.
 


#17
There's also plan B on that one TorrentG ... in hardware manager right click the disk controller and uninstall it... reboot the computer, make your BIOS changes, and reboot again... when it does reload windows it should replace the missing disk controller with the correct one.
 


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sameh83

Well-Known Member
#18
Can i do these steps and change my current settings without having to reinstall windows ?
 


#19
Correct answer: Maybe.

Have a full backup of all your data on external storage before you start and don't be surprised if either of our solutions gives you problems.
 


sameh83

Well-Known Member
#20
Well, where can i find the AHCI driver ? i looked on the Lenovo site but was confused !
 


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