How to disable APIC on Abit nForce boards without Windows install

DriveEuro · Jan 31, 2003, 01:22 AM

Here is a quick fix to disable APIC on Abit nForce boards so that you can have a better overclock. Bacially APIC enables several processors on a single board. It allows IRQs over 15. Disabling APIC (enabling PIC) only allows IRQs 1-15 and makes overclocking on Abit nForce boards so much easier and better. Personally my board is stuck at 1750mhz. I can't go higher. With APIC disabled I should be able to clock MUCH higher. I'm going to try it now. Here is the link.

http://forum.abit-usa.com/showthread...&threadid=3032

Dyre Straits · Jan 31, 2003, 03:55 PM

I know this is nitpicky, but, when you limit the IRQs it's 0-15, which makes a total of 16.

Dyre Straits

RIV@NVX · Jan 31, 2003, 04:48 PM

Report here - I will check for that option on my KT3 Ultra... not sure.

DriveEuro · Jan 31, 2003, 05:15 PM

Well, I did that... After I performed this it shoulda helped me OC higher. Nada. Didn't do shit for me. It is supposed to help raise FSB mostly.

ToshiroOC · Jan 31, 2003, 05:29 PM

Well, that means its your processor thats not too good at OCing, not your motherboard

IRQs couldn't matter less to a perfectly stable motherboard if its the CPU crapping out on ya... guess you just got a bad sample. Better luck next time!

Dyre Straits · Jan 31, 2003, 06:00 PM

My P4 1.6 overclocks very nicely to 1.76. But that's as high as I can go and keep a stable system....or even get a boot screen for that matter.

This is with APIC on, too. I haven't tried turning it off.

Dyre Straits

DriveEuro · Jan 31, 2003, 07:45 PM

No, this APIC thing applies to Abit Socket A motherboards.

Rayder · Jan 31, 2003, 08:47 PM

On my motherboard, I had to turn off APIC mode just to get it to setup correctly. When I tried having it on for setup, I kept getting wierd lock-ups and crashes. I DO remember reading somewhere though that it's one setting that shouldn't be played with after setup, it didn't say why but I could guess.....

RIV@NVX · Jan 31, 2003, 08:51 PM

Well, that option EXISTS in my KT3 Ultra BIOS, but I don't really want to experiment with it - my Audigy is very sensitive card on IRQ/blah/blah, and some devices have IRQ more than 16... it isn't worth it, at least for me - I guess.

DriveEuro · Jan 31, 2003, 08:54 PM

If you installed XP with APIC enabled then once diasabled after install XP WILL NOT START.

ToshiroOC · Jan 31, 2003, 08:57 PM

Driveeuro, sorry, but you are wrong. I have APIC disabled on my mobo (more because it was causing some minor stability issues than for OCing), and I did it retroactively for XP... and it changed nothing major except for what it was supposed to, and made it so I have to manually click off my PSU after shutting down...

DriveEuro · Jan 31, 2003, 09:06 PM

Um, are you talking about ACPI? Cuz the APIC and ACPI are totally different. APIC has nothing to do with power...just IRQs

RIV@NVX · Jan 31, 2003, 09:19 PM

Quote:

Originally posted by DriveEuro
If you installed XP with APIC enabled then once diasabled after install XP WILL NOT START.

It will if you do as you told in your first post, right?

DriveEuro · Jan 31, 2003, 09:31 PM

Yes it will if you do what the first post...or the link...says. I did it. Change your APIC driver, then disable APIC in the bios... But I said that this only helps ABIT boards. No need trying it if your overclock is fine. Besides not many boards even have this setting. APIC is designed for multiprocessors. How many nForce2 boards have dual processors? None that I know of.

Jan 31, 2003, 01:22 AM	#1
DriveEuro HardwareHeaven Extreme Member Join Date: Jul 2002 Location: Gurnee Illinois Posts: 4,677 Rep Power: 0	How to disable APIC on Abit nForce boards without Windows install Here is a quick fix to disable APIC on Abit nForce boards so that you can have a better overclock. Bacially APIC enables several processors on a single board. It allows IRQs over 15. Disabling APIC (enabling PIC) only allows IRQs 1-15 and makes overclocking on Abit nForce boards so much easier and better. Personally my board is stuck at 1750mhz. I can't go higher. With APIC disabled I should be able to clock MUCH higher. I'm going to try it now. Here is the link. http://forum.abit-usa.com/showthread...&threadid=3032 __________________ [color=orange]ASUS P4P800 Deluxe [color=black]-[/color] 2.4C --> 3300mhz [color=black]-[/color] Mushkin PC3200 at 220 5-2-2-2 (cpu limited) [color=black]-[/color] BBAti 9800Pro at 430/375 [/color] [color=black]3[/color][color=gray]D[/color]M[color=black]a[/color][color=gray]r[/color]k[color=yellow]01[/color] [color=black]3[/color][color=gray]D[/color]M[color=black]a[/color][color=gray]r[/color]k[color=yellow]03[/color] 16001200 12801024

Jan 31, 2003, 04:48 PM	#3
RIV@NVX Freedom is a feature. Join Date: Jul 2002 Location: Croatia, Rijeka Posts: 4,476 Rep Power: 0 System Specs	Report here - I will check for that option on my KT3 Ultra... not sure. __________________ -- Vedran

Jan 31, 2003, 05:15 PM	Thread Starter #4
DriveEuro HardwareHeaven Extreme Member Join Date: Jul 2002 Location: Gurnee Illinois Posts: 4,677 Rep Power: 0	Well, I did that... After I performed this it shoulda helped me OC higher. Nada. Didn't do shit for me. It is supposed to help raise FSB mostly. __________________ [color=orange]ASUS P4P800 Deluxe [color=black]-[/color] 2.4C --> 3300mhz [color=black]-[/color] Mushkin PC3200 at 220 5-2-2-2 (cpu limited) [color=black]-[/color] BBAti 9800Pro at 430/375 [/color] [color=black]3[/color][color=gray]D[/color]M[color=black]a[/color][color=gray]r[/color]k[color=yellow]01[/color] [color=black]3[/color][color=gray]D[/color]M[color=black]a[/color][color=gray]r[/color]k[color=yellow]03[/color] 16001200 12801024

Jan 31, 2003, 05:29 PM	#5
ToshiroOC Unbiased. Join Date: Jun 2002 Posts: 4,812 Rep Power: 0	Well, that means its your processor thats not too good at OCing, not your motherboard IRQs couldn't matter less to a perfectly stable motherboard if its the CPU crapping out on ya... guess you just got a bad sample. Better luck next time! __________________ [img][/img] [color=White]Peace be with you, Joe.[/color] Driverheaven Staff Member (Supermoderator)

Jan 31, 2003, 07:45 PM	Thread Starter #7
DriveEuro HardwareHeaven Extreme Member Join Date: Jul 2002 Location: Gurnee Illinois Posts: 4,677 Rep Power: 0	No, this APIC thing applies to Abit Socket A motherboards. __________________ [color=orange]ASUS P4P800 Deluxe [color=black]-[/color] 2.4C --> 3300mhz [color=black]-[/color] Mushkin PC3200 at 220 5-2-2-2 (cpu limited) [color=black]-[/color] BBAti 9800Pro at 430/375 [/color] [color=black]3[/color][color=gray]D[/color]M[color=black]a[/color][color=gray]r[/color]k[color=yellow]01[/color] [color=black]3[/color][color=gray]D[/color]M[color=black]a[/color][color=gray]r[/color]k[color=yellow]03[/color] 16001200 12801024

Jan 31, 2003, 08:47 PM	#8
Rayder Mostly lurking lately.... Join Date: Jun 2002 Location: U.S.A. Posts: 2,161 Rep Power: 73	On my motherboard, I had to turn off APIC mode just to get it to setup correctly. When I tried having it on for setup, I kept getting wierd lock-ups and crashes. I DO remember reading somewhere though that it's one setting that shouldn't be played with after setup, it didn't say why but I could guess.....

Jan 31, 2003, 08:51 PM	#9
RIV@NVX Freedom is a feature. Join Date: Jul 2002 Location: Croatia, Rijeka Posts: 4,476 Rep Power: 0 System Specs	Well, that option EXISTS in my KT3 Ultra BIOS, but I don't really want to experiment with it - my Audigy is very sensitive card on IRQ/blah/blah, and some devices have IRQ more than 16... it isn't worth it, at least for me - I guess. __________________ -- Vedran

Jan 31, 2003, 08:54 PM	Thread Starter #10
DriveEuro HardwareHeaven Extreme Member Join Date: Jul 2002 Location: Gurnee Illinois Posts: 4,677 Rep Power: 0	If you installed XP with APIC enabled then once diasabled after install XP WILL NOT START. __________________ [color=orange]ASUS P4P800 Deluxe [color=black]-[/color] 2.4C --> 3300mhz [color=black]-[/color] Mushkin PC3200 at 220 5-2-2-2 (cpu limited) [color=black]-[/color] BBAti 9800Pro at 430/375 [/color] [color=black]3[/color][color=gray]D[/color]M[color=black]a[/color][color=gray]r[/color]k[color=yellow]01[/color] [color=black]3[/color][color=gray]D[/color]M[color=black]a[/color][color=gray]r[/color]k[color=yellow]03[/color] 16001200 12801024

Jan 31, 2003, 08:57 PM	#11
ToshiroOC Unbiased. Join Date: Jun 2002 Posts: 4,812 Rep Power: 0	Driveeuro, sorry, but you are wrong. I have APIC disabled on my mobo (more because it was causing some minor stability issues than for OCing), and I did it retroactively for XP... and it changed nothing major except for what it was supposed to, and made it so I have to manually click off my PSU after shutting down... __________________ [img][/img] [color=White]Peace be with you, Joe.[/color] Driverheaven Staff Member (Supermoderator)

Jan 31, 2003, 09:06 PM	Thread Starter #12
DriveEuro HardwareHeaven Extreme Member Join Date: Jul 2002 Location: Gurnee Illinois Posts: 4,677 Rep Power: 0	Um, are you talking about ACPI? Cuz the APIC and ACPI are totally different. APIC has nothing to do with power...just IRQs __________________ [color=orange]ASUS P4P800 Deluxe [color=black]-[/color] 2.4C --> 3300mhz [color=black]-[/color] Mushkin PC3200 at 220 5-2-2-2 (cpu limited) [color=black]-[/color] BBAti 9800Pro at 430/375 [/color] [color=black]3[/color][color=gray]D[/color]M[color=black]a[/color][color=gray]r[/color]k[color=yellow]01[/color] [color=black]3[/color][color=gray]D[/color]M[color=black]a[/color][color=gray]r[/color]k[color=yellow]03[/color] 16001200 12801024

Jan 31, 2003, 09:31 PM	Thread Starter #14
DriveEuro HardwareHeaven Extreme Member Join Date: Jul 2002 Location: Gurnee Illinois Posts: 4,677 Rep Power: 0	Yes it will if you do what the first post...or the link...says. I did it. Change your APIC driver, then disable APIC in the bios... But I said that this only helps ABIT boards. No need trying it if your overclock is fine. Besides not many boards even have this setting. APIC is designed for multiprocessors. How many nForce2 boards have dual processors? None that I know of. __________________ [color=orange]ASUS P4P800 Deluxe [color=black]-[/color] 2.4C --> 3300mhz [color=black]-[/color] Mushkin PC3200 at 220 5-2-2-2 (cpu limited) [color=black]-[/color] BBAti 9800Pro at 430/375 [/color] [color=black]3[/color][color=gray]D[/color]M[color=black]a[/color][color=gray]r[/color]k[color=yellow]01[/color] [color=black]3[/color][color=gray]D[/color]M[color=black]a[/color][color=gray]r[/color]k[color=yellow]03[/color] 16001200 12801024