Windows 7 Forums
Welcome to Windows 7 Forums. Our forum is dedicated to helping you find support and solutions for any problems regarding your Windows 7 PC be it Dell, HP, Acer, Asus or a custom build. We also provide an extensive Windows 7 tutorial section that covers a wide range of tips and tricks.


Windows 7: AHCI mode

25 Dec 2009   #1

 
AHCI mode

Does Windows 7 still require AHCI be configured before installation? I think in XP if you switched an SATA drive to AHCI from IDE, you would need to format and start over.


My System SpecsSystem Spec
.

26 Dec 2009   #3

 

Thanks Greg - that is informative. So I guess the next question is, if I'm not going to be hot-swapping, is there really any benefit to AHCI?
My System SpecsSystem Spec
.


26 Dec 2009   #4

 

And another one for you while you are here - can PW move a Windows 7 installation? I have a newer IDE drive to replace the aged dinosaur on my kids' computer, and it wouldn't hurt my feelngs if I didn't have to do a full reinstall, since it has 4 user accounts on it.
My System SpecsSystem Spec
26 Dec 2009   #5
Microsoft MVP

 

Well what caught my eye there is the AHCI added Power Management capabilities.

I think it is the optimal, but there is a lively debate around here about whether it is that much better than IDE.

The last half dozen efforts to change to AHCI to overcome install errors have failed here. It worked once last week.
My System SpecsSystem Spec
26 Dec 2009   #6
Microsoft MVP

 

Quote   Quote: Originally Posted by RogerR View Post
And another one for you while you are here - can PW move a Windows 7 installation? I have a newer IDE drive to replace the aged dinosaur on my kids' computer, and it wouldn't hurt my feelngs if I didn't have to do a full reinstall, since it has 4 user accounts on it.
Yes, it can delete, mark active/inactive, convert logical, resize, move, copy, check file system and scan HD surface.

We use it all the time here to delete dual boot XP/Vista off first partition, resize Windows 7 into that space, even jump Windows 7 over a middle data partition or from another HD into first partition space.

Start by your posting back a screenshot of the full Disk Management map.
My System SpecsSystem Spec
26 Dec 2009   #7

 

Quote   Quote: Originally Posted by RogerR View Post
Does Windows 7 still require AHCI be configured before installation? I think in XP if you switched an SATA drive to AHCI from IDE, you would need to format and start over.
You do not need to format and start over, you just have to change a registry then change the bios. How to enable AHCI in Windows 7 RC after installation | ithinkdifferent will explain how.
I just did that a few hours ago and didn't have any performance increase so I just turned it back to IDE.
My System SpecsSystem Spec
27 Dec 2009   #8

Windows 7 Home Premium 64bit
 
 

When I was running my OS on my WD640AAKS HD, there was no difference in performance what-so-ever betweeen IDE and AHCI. Well, maybe like 3MB/s read faster. Not really any benefit.

However, when I switched to a SSD, for some reason it made a difference.
The SSD was 15mb/s faster read and 10mb/s faster write under ICHR.

Alot also depends on your motherboard and chipset, so each system will respond differently.


IMO, your best option if your really curious about permance, is do the registry hack
(if you installed under IDE) so you theres no need to re-install.
If you install Windows 7 under AHCI mode, you can easliy just switch back to IDE.

Boot up under IDE mode. Gives Windows 5min to finish pre-fetching etc.
Benchmark your HD's under IDE mode and remember the score.
Do this again under AHCI mode.

You will then have your answer for your particular machine/setup which offers better performance.

If the results are the same or minimal, Id just use IDE for compatability reasons.
My System SpecsSystem Spec
27 Dec 2009   #9

 

There's no disadvantage to AHCI. No downsides at all. NCQ has been shown to have it's advantages - but for anyone who possesses an external SATA dock or drive, the hotswap ability is a quintessential feature.
My System SpecsSystem Spec
27 Dec 2009   #10

 

Quote   Quote: Originally Posted by Wishmaster View Post
If the results are the same or minimal, Id just use IDE for compatability reasons.
Compatibility with ..?

All my drives are SATA.
My System SpecsSystem Spec
Reply

 AHCI mode




Thread Tools



Similar help and support threads for2: AHCI mode
Thread Forum
SSD problems in AHCI mode Hardware & Devices
Sata Mode AHCI / IDE Hardware & Devices
Solved Can I switch my boot disk from ahci mode to raid mode? Hardware & Devices
AHCI Mode Setup Hardware & Devices
Solved Can't Boot from CD-ROM in AHCI mode Installation & Setup
How to check IDE or AHCI mode? General Discussion
SB600 ATI RAID AHCI drivers? (BSOD on boot if in RAID/AHCI mode.) Drivers

Our Sites

Site Links

About Us

Find Us

Windows 7 Forums is an independent web site and has not been authorized, sponsored, or otherwise approved by Microsoft Corporation. "Windows 7" and related materials are trademarks of Microsoft Corp.

Designer Media Ltd

All times are GMT -5. The time now is 01:41 PM.
Twitter Facebook Google+



Windows 7 Forums

Seven Forums Android App Seven Forums IOS App
  

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33