Make sure your hdd mode is set to ahci for SSD's

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I just had to "upgrade" a computer the hdd was making clanking noises and was dying.

after backing up the hdd then imaging it to the ssd I found out it was set to ide mode..

to change it to ahci you have to (good idea for any sata hdd really)
Quote:


The following technique can be used to switch between IDE-mode and AHCI-mode (the native mode for SATA) drivers in Vista or Windows 7:

1) Run the Registry Editor (regedit.exe)
2) Navigate to Registry Key: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Msahci
3) Set the "Start" value to 0 (zero)
4) Navigate to Registry Key: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Pciide
5) Set the "Start" value to 0 (zero)
6) Shut down
7) Start up again, but before Windows boots go into the BIOS configuration screens and change the disk mode to "AHCI". Save the new BIOS configuration and restart so that Windows boots.

When Windows starts, it will detect the change, load new disk drivers, and do one more reboot to start up with them.

Credit:
sminlal from tomshardware forums.


Before and after benchmark using samsung magician 4



samsungperfcap-idetoahci.jpg


final notes: no other hdd makes a clanking noise quite like the ibm/hitachi deathstar.

Computer was a AMD Phenom II960T@3ghz,8gb ram
 
This is something you do want to do, but you need to be careful. If you change from IDE to AHCI with an existing windows install, you are going to have a bad time, because it is not going to boot. It will probably say please insert disk, or MBR not found, or something like that. You really want to do this on a fresh install of windows ideally.
 
Originally Posted By: Nick R
This is something you do want to do, but you need to be careful. If you change from IDE to AHCI with an existing windows install, you are going to have a bad time, because it is not going to boot. It will probably say please insert disk, or MBR not found, or something like that. You really want to do this on a fresh install of windows ideally.

That's why he gave the instructions to make Windows load the correct driver.
 
Originally Posted By: Colt45ws
Originally Posted By: Nick R
This is something you do want to do, but you need to be careful. If you change from IDE to AHCI with an existing windows install, you are going to have a bad time, because it is not going to boot. It will probably say please insert disk, or MBR not found, or something like that. You really want to do this on a fresh install of windows ideally.

That's why he gave the instructions to make Windows load the correct driver.


Yes he did, however I still generally only recommend it on a fresh install, as I've had windows throw a fit when trying to change it after the fact, even when following the process listed.
 
Was this not on an Intel board? I can't count how many Intel RST based boards I've done this on with success.

I had to do a similar procedure when I went from ACHI to RAID.
 
it was an amd phenom II I dont remember the board.

nick: the error messages you list aren't relevant to this. It wont say insert disk or mbr not found or anything like that.

if done incorrectly it will black screen and reboot

it fails partway into loading windows if the registry change isnt made.

Obviously: you want to backup first but if the alternative is a fresh install of windows. you aren't out anything to try this.(never had it fail)
 
Is this relevant to Linux users? I just swapped an old SATA II HDD for a SSD and am curious...
 
Originally Posted By: gathermewool
Should pciide be set to 0 or 3?


what are you doing?

if you are changing it from ide to ahci

you need to set both to 0 as specified in the instuctions

reboot

enter the bios and set mode to ahci

then boot into windows ahci will be detected, and drivers installed

then reboot again..

as stated in the instructions.

doing this wrong may cause you to have to reinstall windows.
 
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Currently, I have AHCI set to a value of 0, PCI IDE set to 3 (HDD, not SSD.) I don't know much, so I was curious about the difference between the instruction and my current configuration.
 
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Originally Posted By: gathermewool
Currently, I have AHCI set to a value of 0, PCI IDE set to 3 (HDD, not SSD.) I don't know much, so I was curious about the difference between the instruction and my current configuration.



you need to include type/model of computer etc.

offhand I'd guess its in ide mode, nothing really wrong with that but its lower performance.

even a regular sata hdd can benefit from ahci, just not as much as a SSD.


note: if you do this wrong you may have to reinstall windows.
 
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HP DM1Z with a 320GB Hitachi Travelstar 7K500 7200RPM HDD.

With the settings I listed above, it makes me think that my HDD is currently running in AHCI (value of 0, ON) and PCIIDE set to a value of 3, OFF. Is that correct?
 
just look in the bios.

the one that was in ide mode was set to 0-ahci and 3 pciide
 
I've had this process work 100% of the time, many, many times.

In fact in this thread is the first I've heard of it not working, much less seeing it for myself.
 
Bump for a question:

So I checked what type of SATA set up I have on my T520 ThinkPad, (i7 Sandybridge CPU):

It's showing AHCI, which means HDD mode is ALREADY set to AHCI; am I correct? (basing this on what I read in several places that if it was NOT set to AHCI, this "SATA AHCI controller" part would NOT show up under SATA controllers...)


I am getting ready to change my HDD to a SSD soon, and want to make sure everything is set for it.
I might also up the RAM from 8 GB to 16 GB...
(I also updated the driver for the AHCI controller today with system update, but i don't think it was any major update - just performance enhancements, etc)
 
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Originally Posted By: 97tbird
Bump for a question:

So I checked what type of SATA set up I have on my T520 ThinkPad, (i7 Sandybridge CPU):

To be absolutely sure, just go into BIOS and check there.
 
Originally Posted By: Nick R
It really makes a huge difference, especially if you are running on a SATA 6gbps system. It's the difference between 240MB/s and 500+MB/s


not in my specific case. it was a decent boost but nothing like 210% speed
The only thing that went up a ton was random iops read. Actual speeds in MB/s not so much

I'm sure it varies widely by sata controller/mobo and device.
samsungperfcap-idetoahci.jpg
 
Originally Posted By: Rand
not in my specific case. it was a decent boost but nothing like 210% speed
The only thing that went up a ton was random iops read. Actual speeds in MB/s not so much

The speeds you're showing look like SATA 2.0. I think Nick was specifically referring to SATA 3.0 (6 Gbps) setups.
 
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