9/26/07

Enable Nvidia AGP Fast Writes and Side Band Addressing on ubuntu Feisty

Today I found tutorial about turn on AGP Fast Writes and Side Band Addressing on nvidia graphic card that not enable by default[ my SBA is already enable, don't know why? ]. Even I'm not sure what it for? I guess it's something that increase 3D performance. Anyway I still want to enable it if my card can support. Since last time I play with my graphic card, my status is

pnix@pnix-a7n:~$ cat /proc/driver/nvidia/agp/status
Status: Enabled
Driver: NVIDIA
AGP Rate: 8x
Fast Writes: Disabled
SBA: Enabled

First check that your card and motherboard are support by
pnix@pnix-a7n:~$ cat /proc/driver/nvidia/agp/card
Fast Writes: Supported
SBA: Supported
AGP Rates: 8x 4x
Registers: 0xff000e1b:0x1f004302
pnix@pnix-a7n:~$ cat /proc/driver/nvidia/agp/host-bridge
Host Bridge: PCI device 10de:01e0
Fast Writes: Supported
SBA: Supported
AGP Rates: 8x 4x
Registers: 0x1f00421b:0x00000302
pnix@pnix-a7n:~$

or there is the newer way
pnix@pnix-a7n:~$ cat /proc/driver/nvidia/registry
VideoMemoryTypeOverride: 1
EnableVia4x: 0
EnableALiAGP: 0
NvAGP: 3
ReqAGPRate: 15
EnableAGPSBA: 0
EnableAGPFW: 0

SoftEDIDs: 1
Mobile: 4294967295
ResmanDebugLevel: 4294967295
FlatPanelMode: 0
DevicesConnected: 0
RmLogonRC: 1
VbiosFromROM: 0
ModifyDeviceFiles: 1
DeviceFileUID: 0
DeviceFileGID: 0
DeviceFileMode: 438
RemapLimit: 0
UseCPA: 4294967295
DetectPrimaryVga: 1
SaveVBios: 0
EnableBrightnessControl: 0
PanelPWMFrequency: 1018
PanelBrightnessLimits: 65280
RMEdgeIntrCheck: 1
pnix@pnix-a7n:~$

now my current frame rate is about
pnix@pnix-a7n:~$ glxgears -info
GL_RENDERER = GeForce 6200/AGP/SSE/3DNOW!
GL_VERSION = 2.1.0 NVIDIA 96.31
GL_VENDOR = NVIDIA Corporation
GL_EXTENSIONS = GL_ARB_color_buffer_float GL_ARB_depth_texture GL_ARB_draw_buffers
.
.
GL_SGIS_generate_mipmap GL_SGIS_texture_lod GL_SGIX_depth_texture GL_SGIX_shadow GL_SUN_slice_accum
8405 frames in 5.0 seconds = 1680.943 FPS
8117 frames in 5.0 seconds = 1623.218 FPS
7256 frames in 5.0 seconds = 1451.083 FPS
8248 frames in 5.0 seconds = 1649.593 FPS
7872 frames in 5.0 seconds = 1574.323 FPS
7993 frames in 5.0 seconds = 1598.514 FPS
8243 frames in 5.0 seconds = 1648.591 FPS
8300 frames in 5.0 seconds = 1659.995 FPS
6721 frames in 5.0 seconds = 1344.161 FPS
8324 frames in 5.0 seconds = 1664.768 FPS
8337 frames in 5.0 seconds = 1667.350 FPS
8479 frames in 5.0 seconds = 1695.651 FPS

To turn on those two option you need to edit '/etc/modprobe.d/nvidia-kernel-nkc' file. Open it with your favorite text editor and make it look like this.
alias char-major-195* nvidia
options nvidia NVreg_EnableAGPFW=1 NVreg_EnableAGPSBA=1

then reboot.
After it come back on, I can't see noticable change. except
pnix@pnix-a7n:~$ cat /proc/driver/nvidia/agp/status
Status: Enabled
Driver: NVIDIA
AGP Rate: 8x
Fast Writes: Enabled
SBA: Enabled

ref: original howto on gentoo-wiki

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