Hi, that's a cute little board! But why you want to use AHCI ?

AHCI or ACPI? I often make posts about using an early version of XP and disabling ACPI as it reduces performance.

Logistics wrote:

AHCI or ACPI? I often make posts about using an early version of XP and disabling ACPI as it reduces performance.

But would be stupid to disable ACPI in a relative modern board like in OP's case. Disabling ACPI is such board messes with the resource assignation and configuration of the integrated devices, like USB2 ports and the integrated HDA audio functions, with almost no performance gains, specially if your board has a lot of USB/SATA ports, and you also want to use the PCI slots. In effect, in many of these boards the manufacturer doesn't offer the function to disable ACPI anymore.

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As for AHCI, Intel offers boot time drivers for XP OS and upwards, called sometimes F6 drivers, because you need press F6 at XP text mode install time to invoke the OS function to load and install them so you can see and use the HDDs attached to these controllers at setup time.

Of course, you can disable AHCI and use these drives as PATA disks, but i recommend you to no do that, if isn't absolutely necessary. Better find and use the drivers which Intel provides for the OS.

What issues are you worried about?

AHCI gets you NCQ and hotplug. NCQ is something I've never really been able to feel, especially with hard drives where it can actually be slower. Some older hard drives don't respond well to NCQ. If you want hotplug though then yeah AHCI is nice. 😀

I thought it might have something to do with using IDE or SATA drives, where it would cause problems with one or the other. I'm kinda new to all this so overlook it if I'm way off base!

AHCI is pretty much SATA native.

Most boards give the option of

IDE/LEgacy
AHCI
Raid

Always go with AHCI unless you need to setup a raid. Legacy/IDE is only for if your OS doesn't have the drivers and they dont exist or your just to lazy to hook up a floppy drive.

hyoenmadan wrote:

But would be stupid to disable ACPI in a relative modern board like in OP's case. Disabling ACPI is such board messes with the resource assignation and configuration of the integrated devices, like USB2 ports and the integrated HDA audio functions, with almost no performance gains, specially if your board has a lot of USB/SATA ports, and you also want to use the PCI slots. In effect, in many of these boards the manufacturer doesn't offer the function to disable ACPI anymore.

The last time I did a no-ACPI install of XP was on a Socket 478 system with a 2GHz P4. I don't remember what games I was playing at the time, but it was about an 8-10 f.p.s. increase in each title. And it doesn't cause problems with resource assignment, instead it keeps XP from forcing resource sharing. My system had USB 2.0 and integrated audio, but not SATA. In any case, the only thing you lose is the ability to make the system Sleep/Hibernate, and you had to press the power button to actually power-down the system after you shut down Windows. Big woop.

Logistics wrote:

The last time I did a no-ACPI install of XP was on a Socket 478 system with a 2GHz P4. I don't remember what games I was playing at the time, but it was about an 8-10 f.p.s. increase in each title. And it doesn't cause problems with resource assignment, instead it keeps XP from forcing resource sharing. My system had USB 2.0 and integrated audio, but not SATA. In any case, the only thing you lose is the ability to make the system Sleep/Hibernate, and you had to press the power button to actually power-down the system after you shut down Windows. Big woop.

The i945 which OP has isn't your average 478 mobo. Also your never told which chipset were you using.
Also, your performance problem sounds more a Chipset/BIOS/Video/Driver problem than a ACPI matter.

Logistics wrote:

instead it keeps XP from forcing resource sharing.

If you have a motherboard with a proper XP compliant ACPI implementation, ACPI will use APIC to assign higher IRQs to all integrated peripherals while reserving lower "PC-Legacy" ones for system devices and PCI cards. There aren't resource sharing on lower IRQs as you can see.

Logistics wrote:

In any case, the only thing you lose is the ability to make the system Sleep/Hibernate, and you had to press the power button to actually power-down the system after you shut down Windows. Big woop.

You don't seem to understand what is ACPI at all and you're confusing it with the ATX specification software power off feature.
http://wiki.osdev.org/ACPI

on 2 systems i used so far with AHCI, standard IDE was visibly slower than native mode; and those were not even the newer sata versions;

mrau wrote:

on 2 systems i used so far with AHCI, standard IDE was visibly slower than native mode; and those were not even the newer sata versions;

What machines were you using? I always wondered about how much of a difference it really makes.

the first one was a p4 with a rather good workstation motherboard, i cant remember the model though; the other one i use now, its a GigaByte GA-990XA-UD3

hyoenmadan wrote:

The i945 which OP has isn't your average 478 mobo. Also your never told which chipset were you using.
Also, your performance problem sounds more a Chipset/BIOS/Video/Driver problem than a ACPI matter.

I was using the i845 chipset. And your the first person I've heard refer to this scenario as a "performance problem." It's simply something other users and I did, back then to increase our performance in XP.

If you have a motherboard with a proper XP compliant ACPI implementation, ACPI will use APIC to assign higher IRQs to all integrated peripherals while reserving lower "PC-Legacy" ones for system devices and PCI cards. There aren't resource sharing on lower IRQs as you can see.

You don't seem to understand what is ACPI at all and you're confusing it with the ATX specification software power off feature.
http://wiki.osdev.org/ACPI

What you're saying could be completely true. But my understanding of ACPI really doesn't have anything to do with it. I'm simply describing what the effect of disabling ACPI was for my system, years ago. I got a performance boost, but lost the ability to hibernate/sleep and to cause the system to power itself down through software.

More importantly, your continued speculation on what "should" and "should not" be happening is not productive nor constructive. Plus, you'll notice that I never suggested that the OP should disable ACPI, I only asked if that is what he was referring to in the original post since I have mentioned it a few times, whereas I have not seen many people mention disabling AHCI. I only described my situation because you seemed to feel it was necessary to defend your opinion on disabling ACPI on a new system, which nobody suggested anyone should do. You prompted me to relate my experience, remember?

I don't know that anyone can even build a modern system with disabled ACPI since I believe XP SP1 was the last version of Windows which allowed it, and how new of a system can you make run on XP SP1? 🤣

mrau wrote:

the first one was a p4 with a rather good workstation motherboard, i cant remember the model though; the other one i use now, its a GigaByte GA-990XA-UD3

Good to know, thank you 😀

Nice AM3+ board! I like how AMD's latest and greatest still has XP support without issues 😀

quite frankly, it's my impression that xp does not cope well with this machine, the loads were higher for me than on windows 7 - but that may be coincidence, the software environments were not identical; then again on windows 7 I/O gets slower - or at least i do have the impression the harddisk runs a lot more before i see the program i wanna run;
in the end im think quite often about moving to scsi with bbu cache - i had one machine with a compaq smart and it flew;