AGP Fast write and SiS 735 not supported ?

[Chojin]

Hello,

I was just about to upgrade to the latest driver build 3123 from:
NVRM version: NVIDIA NVdriver Kernel Module 1.0-2960 Tue May 14 07:41:42 PDT 2002
GCC version: gcc version 3.1.1

for my /proc/driver/nvidia/cards/0:
Model: GeForce2 GTS
IRQ: 11
Video BIOS: 02.15.01.14
Card Type: AGP

when I saw that currently /proc/driver/nvidia/agp/status:
Status: Enabled
Driver: AGPGART
AGP Rate: 4x
Fast Writes: Disabled <---
SBA: Disabled

with /proc/driver/nvidia/agp/card:
Fast Writes: Supported <---
SBA: Not Supported
AGP Rates: 4x 2x 1x
Registers: 0x1f000017:0x1f000104

but /proc/driver/nvidia/agp/host-bridge:
Host Bridge: SiS 735
Fast Writes: Not Supported <---
SBA: Supported
AGP Rates: 4x 2x 1x
Registers: 0x1f000207:0x00000104

I googled and read that this Board ECS K7S5A should support Fast Write, but there is no bios-setting to switch it on or off :-/

I also tried using the driver's internal AGP and loading the NVdriver with NVreg_EnableAGPFW=1, but that didn't help.

Now my question is, wether it is a missing kernel feature for this chipset or a driver issue ? Could I force use of Fast Write by changing os-registry.c ? Or is it a kernel-related issue about AGP ?

Did anyone manage to enable Fast Write with a geForce 2 and a SiS 735 chipset ?

Any comments are very welcome.

Btw, I couldn't search the forums for "sis AND 735" because of the 4-letter-minimum-search-security feature, thus I hope this hasn't been discussed a million times before ;) Please forgive, if so.

Regards,
Marc

[Thunderbird]

First of all Fast Writes and SBA can be very unstable on some chipsets. (not on all anymore)

For stability reasons these options are most of the time disabled. To use them you can load the kernel module with special options. Like the one you used (NVreg_EnableAGPFW=1). You can also edit os-registry.c of the kernel module source.

For both ways you need to load the kernel module and then startx. After a start of X agp is initialized.

[Chojin]

Hi Thunderbird,

thanks for your fast reply :)

First of all Fast Writes and SBA can be very unstable on some chipsets. (not on all anymore)

Yeah, I read that.. But I thought I'll give it a try, since it's running very smooth on my window$ box with a KT133a chipset and a geForce 3. And maybe I can get a few more frames per second on this SiS735 with geForce 2 for UT2003 =)

For stability reasons these options are most of the time disabled. To use them you can load the kernel module with special options. Like the one you used (NVreg_EnableAGPFW=1). You can also edit os-registry.c of the kernel module source.

Well, NVreg_EnableAGPFW=1 didn't enable Fast Write for me. Reading through os-registry.c I'm think changing the 0 to 1 won't change anything either, because the module parameter NVreg_EnableAGPFW=1 is overwriting that variable anyway :-/

For both ways you need to load the kernel module and then startx. After a start of X agp is initialized.

Sure, on my lfs I have no xdm or something running.

I of course reloaded the driver (with no running X), but no change in /proc/driver/nvidia/agp/*.

I now guess it's not activated because /proc/driver/nvidia/agp/host-bridge says it's not supported.

So still, my question, where is /proc/driver/nvidia/agp/host-bridge getting it's info on wether Fast Write is supported or not ? Is it reading from the used AGP implemenation ?

Since the Option "NvAGP" set to 1 or 2 is not changing anything (and I for sure have agpgart (not loaded for 1 and loaded for 2), either both AGP support-implementation don't want Fast Write on a SiS 735 or the nvidia driver doesn't.

Still, any comments are very welcome :)

Regards,
Marc

[Thunderbird]

After you reload the kernel module you need to start X once to let it initialize AGP again. (needs to be done after each reload else the info in /proc is not good)

[Chojin]

I did that. No chance.

[Chojin]

Ok, now that I have read through nv.c and os-interface.c, and after googling some more, I found out, that Fast Write was disabled by a bios update in 2001 on the ECS K7S5A :-(

I read that the bios version from 010608 should still have Fast Write enabled, but it doesn't support my harddisks.. so, sh*t happens...

Don't buy ECS. They disable things and don't even think it could be important to let the user know...


Thanks for your answers, Thunderbird, though the second answer was a n00b answer anyway...


Regards,
Marc

[kappax]

Originally posted by Chojin
Ok, now that I have read through nv.c and os-interface.c, and after googling some more, I found out, that Fast Write was disabled by a bios update in 2001 on the ECS K7S5A :-(

I read that the bios version from 010608 should still have Fast Write enabled, but it doesn't support my harddisks.. so, sh*t happens...

Don't buy ECS. They disable things and don't even think it could be important to let the user know...


Thanks for your answers, Thunderbird, though the second answer was a n00b answer anyway...


Regards,
Marc


I have a newerbios (hacked one) that they say has fast wirrites, but for the life of me i cant get it to work!!

[Chojin]

Hi kappax :)

I have a newerbios (hacked one) that they say has fast wirrites, but for the life of me i cant get it to work!!

Could you pass it on to me ? Maybe I'll manage to get it working...

Please send me a copy to nvidia at chojin dot dyndns dot org.

Thanks !

Regards,
Marc

[kappax]

Originally posted by Chojin
Hi kappax :)



Could you pass it on to me ? Maybe I'll manage to get it working...

Please send me a copy to nvidia at chojin dot dyndns dot org.

Thanks !

Regards,
Marc


ok, it is a oc bios, :) it let me make my XP1600+ to a xp1800+ in a while i am trying for xp1900+

[Chojin]

Kappax and me managed to get it working with a unofficial bios. He won about 750 frames in glxgears :)

So I suggest everyone with the same problem heads over to OCWorkbench and grab one of their fine bios' ;)

Regards,
Marc