Sata Mode AHCI / IDE

WH4K · 03 Mar 2011

I'm glad to know about the HotSwap utility. Due in part to poor documentation supplied with my motherboard, it was quite a while before I stumbled upon the fact that I needed to operate in AHCI mode to enable hotplugging of eSATA drives (it's possible with internal SATA drives too, but I typically have no need to do that).

I have used an external HDD for a couple of years, and always found it a real pain to have to shut down the system completely to disconnect/reconnect it via eSATA.

Dave76 · 06 Mar 2011

unifex, I installed the newest Intel RAID drivers, this was a few years ago but, the new RST drivers should work.

DeaconFrost said:

We should clear up a few things here. You are correct about the eSATA functionality, but NCQ is a server-related technology, handling multiple requests for disk access at once. It is a largerly useless technology on a single user workstation, and you won't see any difference in disk usage between AHCI and IDE.

Dave76 said:

As long as you have the RAID drivers loaded in the OS it will run in AHCI mode.

You do not want RAID drivers loaded, unless you are referring to a chipset that I'm not familiar with. IDE, AHCI, and RAID are completely separate and independent...and all have separate drivers. For example, with Intel chipset boards, AHCI is picked up by Windows 7, and the chipset drivers install the official drivers from Intel. RAID requires an entirely different BIOS settings and driver package form Intel. They are not one in the same.

You will see some benefits from NCQ.

Some OEM computers, including Dell Inspiron 530 , don't have an AHCI option, only IDE or RAID.
RAID will enable AHCI.

NCQ

Native Command Queuing (NCQ) is a technology designed to increase performance of SATA hard disks under certain conditions by allowing the individual hard disk to internally optimize the order in which received read and write commands are executed. This can reduce the amount of unnecessary drive head movement, resulting in increased performance (and slightly decreased wear of the drive) for workloads where multiple simultaneous read/write requests are outstanding, most often occurring in server-type applications.

Probably is more useful used on a server, but would help home users with HDDs and SSDs.

NCQ is also used in newer solid-state drives where the drive encounters latency on the host, rather than the other way around. For example, Intel's X25-E Extreme solid-state drive uses NCQ to ensure that the drive has commands to process while the host system is busy processing CPU tasks. [3]

NCQ also enables the SSD controller to complete commands concurrently (or partly concurrently, for example using pipelines) where the internal organisation of the device enables such processing.

For example, the SandForce 1200 [4] based OCZ Vertex II 50GB drive running on a Dell Perc 5i (which doesn't support SATA NCQ) delivers about 7,000 4k IOPS (50% write) at a controller queue depth of 32 IOs. Moving the drive to the similar Dell Perc 6i increases this to over 14,000 IOPS on the same basis.

AHCI

Many SATA controllers offer selectable modes of operation: legacy Parallel ATA emulation, standard AHCI mode, or vendor-specific RAID. Intel recommends choosing RAID mode on their motherboards (which also enables AHCI) rather than AHCI/SATA mode for maximum flexibility,

RAID has also become an operating mode in SATA along with AHCI and IDE. In terms of features, it basically exposes the same feature set that is available in AHCI making them identical in single disk applications.
RAID mode in SATA also exposes the same functionality that AHCI does.

From the Intel site:

If you are using a SATA hard drive, the best option is to set your BIOS to RAID mode. RAID mode provides the greatest overall flexibility and upgradeability because it allows your system to be RAID-Ready and also enables AHCI.

AHCI and RAID use different drivers, but you can enable RAID and not have any drives in RAID mode, the drive will be seen as a non-RAID drive.

Golden · 06 Mar 2011

Dave76 said:

but you can enable RAID and not have any drives in RAID mode, the drive will be seen as a non-RAID drive.

100% correct

WH4K · 06 Mar 2011

True, one can operate with the disk controller in RAID mode without actually doing any RAID stuff. I have that option (ICH9R here), but I tried it and didn't like it.

For Windows XP, even if I didn't want to run an actual RAID, I had to install the Intel Matrix Storage Manager software. That was a problem.

Under Windows XP, the Matrix software for some reason caused the system to be unresponsive for a long time after reaching the desktop. Sometimes the delay was as much as a full minute. The delay occurred with a fresh Windows XP install, and regardless of whether I was running a RAID.

Once you'd installed the Matrix software, there was no easy way to uninstall it. It had no uninstaller, and I wasn't sure what would happen if one simply yanked it by editing the registry.

Ultimately, I had to reinstall Windows XP to get rid of Matrix. I later found a way to install AHCI drivers without the Matrix software, so I did that. I have run Windows XP with my disk controller in AHCI mode since then.

That said, the last time I tried the RAID thing was a few years ago. Possibly, Intel's newer Rapid Storage Technology (RST) software doesn't have that unresponsiveness problem with Windows XP.

crovou718 · 18 Dec 2011

Serpentz said:

Hey everyone. I hope everyone is doing fine. I've literally rebuilt my entire machine but I think I made a mistake before installing Windows 7.

I should have gone over the BIOS with a fine tooth comb, but I did not. The SATA mode is set to IDE instead of AHCI or RAID and now of course, I can't switch it to my knowledge without getting a BSOD. It means I would have to reinstall the OS over again.

I have been reading up online and did a search here, but didn't find the appropriate thead. I have two questions. I read on a forum somewhere, where an Intel user used a program to change this in Windows somehow. Is there some kind of utility that will allow me to switch to AHCI mode without reinstalling Win7 64bit?

Second question, is it worth it to switch over? I see the benefits are this:

AHCI mode brings 3 main advantages:
Supports NCQ (Native Command Queuing) allowing SATA drives to accept more than one command at a time and dynamically reorder the commands for maximum efficiency.
Supports hot plugging of devices
Supports staggered spin ups of multiple hard drives at boot time

My machine seems kind of slow when accessing data and don't know if this is an issue with the SATA drives being in IDE mode. I got some choppiness in some games that's coming from access data (tested) and that seems weird but could definitely come from SATA drives being in IDE mode.

I got an MSI R5770 Hawk Video card...I'm freaking in love with that thing :)

I have two Hitachi 7200RPM SATA and one Seagate Barracuda 7200RPM SATA drive. All three are 500GB

My new machine is ASRock M3A770DE Mainboard and I successfully unlocked the 4th core on my AMD Athlon 445 making it a Phenom X4 3.1 and it's running beautifully. Ran a stability test and it was perfect.

RAM is Kingston HyperX CAS8 running at 1600mhz

So my question....to AHCI or not. Do you think its worth it. Have you noticed huge performance gains.

So now I guess I better update my profile and sorry I haven't been around. Me and SevenForums had an email issue

Cheers!

I have the same motherboard... you probably won't see this thread since you posted so long ago, but, was your ext HD working in IDE through eSATA?

Initially, mine did not work in IDE. I installed drivers off the disc, and then it was working in IDE. Then it stopped, I think after I installed Win updates. Now it only works in AHCI mode.

essenbe · 18 Dec 2011

Change to AHCI mode.

crovou718 · 18 Dec 2011

I made a dedicated thread to my issue since its different in nature, and this one is so old:
Why won't my external hard drive work in IDE mode through eSATA?

apollodominion · 19 Dec 2011

Enable AHCI and you will need to reinstall windows but it will run more stable and get more speed but BSOD on sandforce 3 SSDs are still the with the Z68 chipset but will be more fo a rarity
I Run AHCI on all ports for the
5x 3TB Black WD SATA3 @ SATA2
120GB OCZ Agility/Corsair/kingston and old Intel 512GB SATA2 and the Agility and corsair are in RAID

essenbe · 19 Dec 2011

apollodominion said:

Enable AHCI and you will need to reinstall windows but it will run more stable and get more speed but BSOD on sandforce 3 SSDs are still the with the Z68 chipset but will be more fo a rarity
I Run AHCI on all ports for the
5x 3TB Black WD SATA3 @ SATA2
120GB OCZ Agility/Corsair/kingston and old Intel 512GB SATA2 and the Agility and corsair are in RAID

You do not need to reinstall windows to change to AHCI. See the link in post #26 above

billgw · 27 Aug 2012

I have 2 IDE DVD drives (TEAC DV-W516D DVD/CD ReWriter, and TSSTcorp DVD-ROM SH-D162C DVD/CD Reader). Teac is capable of 16X DVD writting. My motherboard Gigabyte Z77-D3H has only SATA II/III slots. So I connected each IDE optical drive to motherboard's SATA II slot using IDE to SATA I adapters (1 adapter per optical drive). Win7 Ultimate 32bit is running, and SATA AHCI is being used.
My question: SATA I = 1.5Gbps = 187.5MB/s (adapter capability) is faster then DVD 16X writting = 177.28Mbps = 22.16MB/s. TDK DVD+R disks tested OK (on other PC) for 16X capability. Why is Nero reporting of only 2.4X and 4X writting speeds?