# KT 400A AGP Problems Resolved

## riprjak

I have noticed many people who, like myself, were having issues getting AGP working with the KT400A. I have an Epox 8k9A9I

I tried the following to no Avail;

Gentoo-Sources rc5

Pfeifer-Sources 2.4.21_r1

vanilla-sources 2.4.21

ac sources at a variety of releases

mm sources at a variety of releases

gs sources current emerge build... cant remember... too tired!!!

Turning OFF AGP v3 in bios

FORCING 4x in bios

Using a 2x AGP card

USing a 4x AGP card

Using an 8x AGP card

Manually setting all allowable aperture sizes from 16 to 128MB.

Trying ~x86 ati-drivers internal AGPGART

All of this failed.

However, installing Development Sources 2.6.0_pre1 and building the native AGP support worked.  Yes, I have lost alot of other nice features from the Gentoo-Sources patch suite, but I do have AGP and DRM (from the kernel drivers, since the xfree-drm ebuild wont work with this kernel).

Unfortunately, whilst DRM is functional and glxinfo confirms this, my glxgears score has dropped from ~2000 to ~200!!!  This I will fix later.  Im just happy the whole thing works.

I hope this offers a ray of hope to those like me who were self inflicting baldness with this issue.

Cheers,

riprjak

----------

## dberkholz

Yep. KT400 support in agpgart is only in 2.5/2.6 kernels now; the backport is in progress and I'm unsure what the progress is.

----------

## lucida

You'd better check your agp mode in glxinfo.

I once got ~200FPS when dri enabled and figured out that the card was running at AGP1x.

----------

## riprjak

 *lucida wrote:*   

> You'd better check your agp mode in glxinfo.
> 
> I once got ~200FPS when dri enabled and figured out that the card was running at AGP1x.

 

Lucida, you appear to have hit the nail on the head...  my card is oddly fluctating from 1x to 2x from reboot to reboot...  guess Ill have to "force" the issue  :Smile: 

err!

riprjak

----------

## ex0

how can I upgrade my kernel to 2.5 or 2.6?

----------

## riprjak

 *ex0 wrote:*   

> how can I upgrade my kernel to 2.5 or 2.6?

 

The simplest method is to

```

cd /usr/portage

emerge sys-kernel/development-sources/kernel_of_your_choice

```

Of course, this is installed with a symbolic link to "linux-beta" in the "/usr/src" directory

then you

```

cd /usr/src/linux-beta

make (either menuconfig, config or xconfig to your liking)

make dep && make clean bzImage module modules_install

```

Note that for kernel 2.6.x replace "make dep" with "make"

the final step is

```

mount /dev/insert_boot_partition_here /boot

cp /usr/src/arch/insert_your_architecture_here/boot/bzImage /boot/bzImage.kernel.2.x.x

(probably /usr/src/arch/i386/boot/bzImage)

```

You dont neet to use my bzImage naming method (of trailing .kernel.release after).  Remember to add this kernel to your grub/lilo as required.

Hope this helps.

Oh! yeah, whatever you do, DONT emerge xfree-drm or other such kernel level ebuilds on top of 2.5 or 2.6 unless the package indicates it is aware of said kernels!!!

err!

riprjak

----------

## ex0

exactly what I was after, I'll try it when I get home, cheers

but how do I know what kernels are available to use for "kernel_of_your_choice" ???

----------

## ginji

i have a KT400 chipset here, works a charm... GF 4 mx420 running @ 4x mode every time. gentoo-sources as my kernel although it did work with the vanilla... dunno what your doing "but mine just worked" TM

----------

## ex0

yeh I think most peoples problem is running it with agp 3.0 (8x) mode, not 2.0 (4x)

----------

## riprjak

 *LKS_frag_em_aussie wrote:*   

> i have a KT400 chipset here, works a charm... GF 4 mx420 running @ 4x mode every time. gentoo-sources as my kernel although it did work with the vanilla... dunno what your doing "but mine just worked" TM

 

First, I have a KT400A (there are differences).  Otherwise I have an Epox 8K9A9I, all I know is that the AGP would not work.  On a huge variety of other kernels, even with AGP_TRY_UNSUPPORTED=1.

my thread is for the assistance of people who were having my problem, not for people who weren't  :Wink: 

err!

riprjak

----------

## riprjak

 *ex0 wrote:*   

> exactly what I was after, I'll try it when I get home, cheers
> 
> but how do I know what kernels are available to use for "kernel_of_your_choice" ???

 

you find what is available as follows 

```

emerge sync (if you haven't done so recently)

ls /usr/portage/sys-kernel/development-sources/*.ebuild

```

select your kernel from this list, I am using 2.6.0_pre1 and it is surprisingly stable, tho not as zippy as the gentoo-sources.  Im sure it will get better.  Im just happy to have working AGP.  

Note, these are DEVELOPMENT sources, they can and probably will have problems and not be as stable as release sources such as gentoo-sources or gs-sources.

err!

riprjak

----------

## riprjak

 *ex0 wrote:*   

> yeh I think most peoples problem is running it with agp 3.0 (8x) mode, not 2.0 (4x)

 

My problem was getting AGP recognised regardless of the mode it was set to (I even installed agp 2x  (old school radeon 7000) and agp 4x  (radeon 8500LE) graphics cards instead of the 8x (nvidia mx440) in my investigations, to no avail).

Forcing AGP 4x and disabling AGP v3.0 in BIOS had no effect...  possibly brand related.

err!

riprjak

----------

## ginji

i would have thought that the minor differences in 400 and 400A wouldn't have made much of a difference... my motherboard is a gigabyte, so it could be brand related... If you have a NVIDIA card you may want to try the nvagp...

----------

## riprjak

 *LKS_frag_em_aussie wrote:*   

> i would have thought that the minor differences in 400 and 400A wouldn't have made much of a difference... my motherboard is a gigabyte, so it could be brand related... If you have a NVIDIA card you may want to try the nvagp...

 

I tend to think it is brand related (well, bios programming related); even though there are apparently register differences in the AGP hardware between the 400 and 400A (according the the tech docs from VIA).  However, I still have issues (noted above) and have to force AGP 4x mode for my 8500LE as some reboots it falls back to AGP 1x; hence I tend to agree that the brand/specific hardware/bios implementation is the key.

Re nvagp, thanks for reminding me; that is one solution I didnt test (for th 440MX).  However, since the actual card I was trying to get working was a 4x Radeon 8500LE, the results may be moot.  For those interested, I will rebuild the box on the weekend and try the nvagp driver with gentoo-sources kernel.

err!

riprjak

BTW : that is an awesome avatar mate... where the hell does it come from??

----------

