# nforce3: No AGP available

## pactoo

Hello,

I am running an nforce3 based amd64 system and somehow AGP refuses to get initialized and thus X is disabling DRI. However, I have no idea, where to enable AGP support, as  make menuconfig does not provide anything AGP related at all besides a non selectable /dev/agpgart option. 

```

linux # grep -i agp .config

CONFIG_AGP=y

CONFIG_AGP_AMD64

# CONFIG_AGP_INTEL is not set=y

```

Running Kernel 2.6.12.x, but same issue with 2.6.11.x series. 

dmesg is a bit more precise:

```

linux # dmesg | grep -i agp

ACPI: PCI Interrupt Routing Table [\_SB_.PCI0.AGPB._PRT]

agpgart: Detected AGP bridge 0

agpgart: Aperture conflicts with PCI mapping.

agpgart: Aperture from AGP @ f0000000 size 4096 MB

agpgart: Aperture too small (0 MB)

agpgart: No usable aperture found.

agpgart: Consider rebooting with iommu=memaper=2 to get a good aperture.

Linux agpgart interface v0.101 (c) Dave Jones

```

However, appending the iommu option to my grub.conf does not help:

```

title=Linux-amd64-broken-agp

root (hd0,0)

kernel /vmlinuz root=/dev/sda2 iommu=memaper=2

```

Finally, my BIOS does not have any Aperture setting. The only AGP related Options are: Init Display /AGP/PCI and AGP Mode Auto/4/8. Thats all. It's a Gigbyte K8NS-Ultra Mainboard

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## hw-tph

I have an nforce3-based laptop (an Compaq R3000 model).

In the kernel configuration, under Device Drivers --> Character Devices, I have selected "/dev/agpgart (AGP Support)" and just a few options down "NVIDIA nforce/nforce2 chipset support", both as modules.

In my /etc/modules/autoload.d/kernel-2.6 I have "nvidia-agp" (without quotes, on a line of its own) to load the nvidia-agp module on boot. Since it relies on the agpgart module that is loaded too by sheer magic.

This enables full AGP support. At least it does for me, on my system. (obligatory disclaimer  :Razz: )

Håkan

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## pactoo

Thanks. My problem is, I cannot enable option AGP support at all. I also cannot disable it, is has an "---" before instead of "[ ]". So no chance to (de)select it at all. 

Nevertheless, it seems, that AGP is detected, but cannot be initialized due to some crappy aperture, whatever this may be. Also .config states that some form of AGP is enabled by default. anyway.  But I have no chance to select any chipset besides AGP_INTEL.

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## hw-tph

Move your /usr/src/linux/.config out of the way (save it for backup and future reference) and make defconfig in /usr/src/linux. Then go to Character Devices in menuconfig and choose your options, set up your other options after that. Some choice you have made in your config must have cancelled out the use of other AGP drivers.

Håkan

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## pactoo

No change. Tried 'make deconfig' as well as 'make mrproper'. AGPGART is not selectable.  Not sure however, wether this is the core problem as at least some form of AGP is detected. 

Necertheless, would you mind posting the output of 'cat /usr/src/linux/.config | grep -i agp', please ?

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## hw-tph

```
hw@devon:~$ grep AGP /usr/src/linux/.config

CONFIG_AGP=m

# CONFIG_AGP_ALI is not set

# CONFIG_AGP_ATI is not set

# CONFIG_AGP_AMD is not set

# CONFIG_AGP_AMD64 is not set

# CONFIG_AGP_INTEL is not set

CONFIG_AGP_NVIDIA=m

# CONFIG_AGP_SIS is not set

# CONFIG_AGP_SWORKS is not set

# CONFIG_AGP_VIA is not set

# CONFIG_AGP_EFFICEON is not set
```

Håkan

----------

## dsd

you have the right option, CONFIG_AGP_AMD64 is the right option for *all* amd64 machines. you should try updating your bios, and after that you should file a bug if it is still reproducable on vanilla-sources-2.6.13_rc6.

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## pactoo

Cheers. My Bios is up to date, so I will try vanilla 2.6.13* kernel after my holiday. Maybe then there is a new bios available, too

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## Faed

I'm seeing exactly the same behaviour on a Gigabyte K8NSC-939 board. the bios revision is release "F5", and "F7" is current on their website. The bios has no setting for agp aperture size. I'm getting the following error at boot:

artoo linux # dmesg | grep -i agp

ACPI: PCI Interrupt Routing Table [\_SB_.PCI0.AGPB._PRT]

agpgart: Detected AGP bridge 0

agpgart: Aperture conflicts with PCI mapping.

agpgart: Aperture from AGP @ e8000000 size 4096 MB

agpgart: Aperture too small (0 MB)

agpgart: No usable aperture found.

agpgart: Consider rebooting with iommu=memaper=2 to get a good aperture.

Linux agpgart interface v0.101 (c) Dave Jones

the error suggestion that I try a different iommu setting had no effect, neither did the dmesg output suggesting I try "pci=routeirq". I've tried building the kernel with framebuffer support, and without framebuffer support.. no difference. Looks like this might be an error endemic to this particular family of gigabyte motherboards... that said, it is the first and only motherboard I've ever seen that doesn't have a bios setting for the agp aperture. Any suggestions about workarounds would be greatly appreciated.

```

```

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## swimmer

A bit late but I discovered that I have exactly the same error with an GA-K8NSC-939 on AMD64 :-/

I tried gentoo-sources from 2.6.13 to 2.6.20 - same result all the time. The strange thing is that I assembled this PC in october 2005 and ran KDE on it without any problem and left it since I did not need it anymore ... after reactivating it this month and running all the updates (gcc-4.1.1/glibc-2.5) I am not able to get X running anymore  :Sad: 

Very annoying since the old PC of my wife broke down and I wanted to use this one as a replacement :-/

Any help?

swimmer

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## deface

What video card do you have? Is this an on-board vga controller?

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## swimmer

Hmpf - sorry :-/

Geforce FX 5200 AGP

Portage 2.1.2.2 (default-linux/amd64/2006.1/desktop, gcc-4.1.1, glibc-2.5-r0, 2.6.20-gentoo-r4 x86_64)

System uname: 2.6.20-gentoo-r4 x86_64 AMD Athlon(tm) 64 Processor 3000+

BIOS: F6 

Any more info?

Greetz

swimmer

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## swimmer

Well - I solved it finally after 3 days of digging in my computer and the internet :-/

There is a hidden key in the BIOS of my GA-K8NSC-939 -> CTRL+F1

If you hit it you get an extra option in the BIOS menu: 'Advanced Chipset Features'

And *there* you can finally change the 'AGP Aperture Size' to a reasonable number!

Solved all my problems  :Wink: 

HTH

swimmer

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## lesking

This worked perfectly for me too.

Les.

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## swimmer

Glad to hear  :Smile: 

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