ACPI and/or APIC

All the other systems I've built over the years had ACPI, and a more
recent one has ACPI or APIC. The system I'm building with a P5B-Plus
gives the option of having one or the other, or both.

My understanding is that APIC creates more IRQs that work with the
standard IRQs to avoid problems that may arise if the IRQ is shared
under ACPI.

I can get along fine with the standard IRQs and don't need expansion for
this system, to be used only as a DAW (Digital Audio Workstation). Is
this the only advantage to APIC, or am I wrong entirely?

"RobV" wrote in message ...
All the other systems I've built over the years had ACPI, and a more
recent one has ACPI or APIC. The system I'm building with a P5B-Plus
gives the option of having one or the other, or both.

My understanding is that APIC creates more IRQs that work with the
standard IRQs to avoid problems that may arise if the IRQ is shared
under ACPI.

I can get along fine with the standard IRQs and don't need expansion for
this system, to be used only as a DAW (Digital Audio Workstation). Is
this the only advantage to APIC, or am I wrong entirely?

It's the only advantage, although the same obviously can't be said
for ACPI. Usually on boards that have an option for ACPI and
where I don't need sleep/hibernation modes or IRQ sharing,
I disable ACPI. At least in my experience doing so helps
performance, esp. PCI I/O card performance.

wrote:
"RobV" wrote in message
...
All the other systems I've built over the years had ACPI, and a more
recent one has ACPI or APIC. The system I'm building with a P5B-Plus
gives the option of having one or the other, or both.

My understanding is that APIC creates more IRQs that work with the
standard IRQs to avoid problems that may arise if the IRQ is shared
under ACPI.

I can get along fine with the standard IRQs and don't need expansion
for this system, to be used only as a DAW (Digital Audio
Workstation). Is this the only advantage to APIC, or am I wrong
entirely?

It's the only advantage, although the same obviously can't be said
for ACPI. Usually on boards that have an option for ACPI and
where I don't need sleep/hibernation modes or IRQ sharing,
I disable ACPI. At least in my experience doing so helps
performance, esp. PCI I/O card performance.

Thanks for the response. So, disable ACPI and enable APIC, right? PCI
I/O performance is very important, since the audio card is PCI.

"RobV" wrote in message ...
wrote:
"RobV" wrote in message
...
All the other systems I've built over the years had ACPI, and a more
recent one has ACPI or APIC. The system I'm building with a P5B-Plus
gives the option of having one or the other, or both.

My understanding is that APIC creates more IRQs that work with the
standard IRQs to avoid problems that may arise if the IRQ is shared
under ACPI.

I can get along fine with the standard IRQs and don't need expansion
for this system, to be used only as a DAW (Digital Audio
Workstation). Is this the only advantage to APIC, or am I wrong
entirely?

It's the only advantage, although the same obviously can't be said
for ACPI. Usually on boards that have an option for ACPI and
where I don't need sleep/hibernation modes or IRQ sharing,
I disable ACPI. At least in my experience doing so helps
performance, esp. PCI I/O card performance.

Thanks for the response. So, disable ACPI and enable APIC, right? PCI
I/O performance is very important, since the audio card is PCI.

I think disabling ACPI will also disable APIC on many (all?) boards.
Specifically turning off APIC results in a small performance gain
(not much, but a bit) and prevents IRQ sharing problems with
poorly written drivers (a pandemic problem with audio controllers).
If you don't need this sharing or sleep/hibernate modes disable both
APIC and ACPI. If you do need this sharing I think you have no
option but to enable both.

wrote:
"RobV" wrote in message
...
wrote:
"RobV" wrote in message
...
All the other systems I've built over the years had ACPI, and a
more recent one has ACPI or APIC. The system I'm building with a
P5B-Plus gives the option of having one or the other, or both.

My understanding is that APIC creates more IRQs that work with the
standard IRQs to avoid problems that may arise if the IRQ is shared
under ACPI.

I can get along fine with the standard IRQs and don't need
expansion for this system, to be used only as a DAW (Digital Audio
Workstation). Is this the only advantage to APIC, or am I wrong
entirely?

It's the only advantage, although the same obviously can't be said
for ACPI. Usually on boards that have an option for ACPI and
where I don't need sleep/hibernation modes or IRQ sharing,
I disable ACPI. At least in my experience doing so helps
performance, esp. PCI I/O card performance.

Thanks for the response. So, disable ACPI and enable APIC, right?
PCI I/O performance is very important, since the audio card is PCI.

I think disabling ACPI will also disable APIC on many (all?) boards.
Specifically turning off APIC results in a small performance gain
(not much, but a bit) and prevents IRQ sharing problems with
poorly written drivers (a pandemic problem with audio controllers).
If you don't need this sharing or sleep/hibernate modes disable both
APIC and ACPI. If you do need this sharing I think you have no
option but to enable both.

No, don't need IRQ sharing since the serial and parallel ports are
disabled, so the only IRQs I need are video, audio card, disk drives and
USB ports. Basically what I have now with a NF7-S running with ACPI
enabled and APIC disabled.

Just waiting for the SATA DVD and system drives to arrive for the new
Core 2 Duo system to be complete. I've been running it to set up the
BIOS and check memory and the E6600 CPU ran fine at 3 GHz with stock
voltage (stock speed is 2.4 GHz). :-)

Thanks again for the info. It's much appreciated!

RobV wrote:
All the other systems I've built over the years had ACPI, and a more
recent one has ACPI or APIC. The system I'm building with a P5B-Plus
gives the option of having one or the other, or both.

My understanding is that APIC creates more IRQs that work with the
standard IRQs to avoid problems that may arise if the IRQ is shared
under ACPI.

I can get along fine with the standard IRQs and don't need expansion
for this system, to be used only as a DAW (Digital Audio
Workstation). Is this the only advantage to APIC, or am I wrong
entirely?

With OSs of today and CPUs of today, both ACPI and APIC are best kept
enabled.
This is what MS has to say as of 2001:
http://www.microsoft.com/whdc/system...f/IO-APIC.mspx

A Google search will turn up more interesting details to chew through.

Egil Solberg wrote:
RobV wrote:
All the other systems I've built over the years had ACPI, and a more
recent one has ACPI or APIC. The system I'm building with a P5B-Plus
gives the option of having one or the other, or both.

My understanding is that APIC creates more IRQs that work with the
standard IRQs to avoid problems that may arise if the IRQ is shared
under ACPI.

I can get along fine with the standard IRQs and don't need expansion
for this system, to be used only as a DAW (Digital Audio
Workstation). Is this the only advantage to APIC, or am I wrong
entirely?

With OSs of today and CPUs of today, both ACPI and APIC are best kept
enabled.
This is what MS has to say as of 2001:
http://www.microsoft.com/whdc/system...f/IO-APIC.mspx

A Google search will turn up more interesting details to chew through.

I'm slapping myself on the wrist for not doing what I've told others to
do: use Google. Although, I was looking for experiences folks have had
with ACPI/APIC, such as what nospam contributed.

Thanks for the link, Egil. A very good explanation of what APIC is and
what it does. It's a better way to sort out interrupt requests from
hardware, especially hardware that doesn't do what it should in regards
to interrupts.

ACPI is power management, especially for laptops and support for CPU
power states to save battery power; hot swappable devices for any system
as well. A really good power point presentation here, at the bottom of
the ACPI Design articles.
http://www.microsoft.com/whdc/system...t/default.mspx

Much appreciated, Egil; thanks again!

"RobV" wrote in message ...
Egil Solberg wrote:
RobV wrote:
All the other systems I've built over the years had ACPI, and a more
recent one has ACPI or APIC. The system I'm building with a P5B-Plus
gives the option of having one or the other, or both.

My understanding is that APIC creates more IRQs that work with the
standard IRQs to avoid problems that may arise if the IRQ is shared
under ACPI.

I can get along fine with the standard IRQs and don't need expansion
for this system, to be used only as a DAW (Digital Audio
Workstation). Is this the only advantage to APIC, or am I wrong
entirely?

With OSs of today and CPUs of today, both ACPI and APIC are best kept
enabled.
This is what MS has to say as of 2001:
http://www.microsoft.com/whdc/system...f/IO-APIC.mspx

A Google search will turn up more interesting details to chew through.

I'm slapping myself on the wrist for not doing what I've told others to
do: use Google. Although, I was looking for experiences folks have had
with ACPI/APIC, such as what nospam contributed.

Thanks for the link, Egil. A very good explanation of what APIC is and
what it does. It's a better way to sort out interrupt requests from
hardware, especially hardware that doesn't do what it should in regards
to interrupts.

According to MS: "APIC Provides Superior Interrupt Architecture".
That's true. But practically, an architecture and a well written driver
that uses the architecture properly are two different things. I know
lots of people who had intermittent audio problems (skipping, sync
issues with video etc) which were solved by disabling APIC and
putting each I/O card on its own hard interrupt.

wrote:

[snip]

According to MS: "APIC Provides Superior Interrupt Architecture".
That's true. But practically, an architecture and a well written
driver
that uses the architecture properly are two different things. I know
lots of people who had intermittent audio problems (skipping, sync
issues with video etc) which were solved by disabling APIC and
putting each I/O card on its own hard interrupt.

I remember when that was a huge issue. By reading about all the
problems, I enabled ACPI only and had no problems with audio on the
system I was building at that time.

I would hope that by now they would work the way they should, especially
with an Intel CPU and Intel chipset. We shall see...