Author Topic: some comments on windows XP + ACPI mode vs STANDARD mode  (Read 2080 times)

Offline chrisNova777

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some comments on windows XP + ACPI mode vs STANDARD mode
« on: September 24, 2017, 05:35:48 PM »

I simply cannot record MIDI in ACPI mode in Windows XP. The timing is horrible--a terrible, annoying quarter-note lag. I was thinking SP2 would fix the problem, but it did not.

Thanks Microsoft. I now have a perfectly good USB audio/MIDI interface (Tascam us-122) that can't perform the most basic of functions because of this unfixable problem. For the umpteenth time, I now have to re-install in Standard PC mode.

What are the disadvantages of installing in Standard PC mode? I've heard it causes instability. Does anyone else here have to run Win XP in Standard PC mode because of this problem?

All I know is this:

I have installed XP in ACPI mode countless times and have ALWAYS had the poor MIDI timing.

And I have installed in Standard PC mode countless times and have always had NO MIDI timing problems whatsoever.

I'd say that has nothing to do with latency or settings within Cubase.

The only reason I'd rather not install in Standard PC is because everybody says not to in Win XP. They say it's not necessary.

As to why they say this and how it relates to me, I have no clue

from rme regarding hammerfall cards

Under Windows XP Microsoft has significantly improved both interrupt handling and ACPI. In most cases the interrupts will not be sharing IRQ 9. Even when, problems like with the above mentioned simultaneous network transmission are no longer found. Furthermore XP operates more reliable and stable using the ACPI mode. Therefore changing to Standard-PC mode under Windows XP is not recommended.

The worst thing to do is to use Standard-PC mode with the latest generation of single CPU motherboards, having an advanced programmable interrupt controller (APIC.) These boards offer 24 interrupts under Windows XP in ACPI mode (else found on dual CPU boards only) - but only 15 when using Standard-PC mode!

Need to reinstall for Standard PC mode? You don't have to. Just select Standard PC as the driver, it'll reboot like 3 times, reinstalling all the drivers for your devices (make sure you got your driver disks ready), and you're done. Going back to APCI from Standard PC mode requires a reinstall.