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tmeyer
11-20-02, 05:55 AM
hello.
why does the nvidia driver dont turn on sba and fast write.
both (mainboard chipset and geforce chip) support sba and fast write.

i850 chipset and geforce 4200.

bwkaz
11-20-02, 06:42 AM
Because if they're on, you may see stability issues. The driver developers wanted to cut as many stability issues as they could out of the picture (this is why the drivers also won't initialize any Via chipsets to 4xAGP -- there are issues with some of them not providing the right voltage to the card or something in 4x mode).

Editing /etc/modules.conf (assuming you use RH or Mandrake -- if not, post which distro and version you have, and I'll be able to help better) and adding options NVdriver NVreg_EnableAGPFW=1 NVreg_EnableAGPSBA=1, then running depmod -a to refresh the module dependencies, both as root, then either removing and reinserting the module, or just rebooting, should turn on SBA and fast writes. However, if you see stability problems, turn these off before you try anything else -- you can turn them off by commenting out the options line (add a # at the beginning of it), rerunning depmod -a, and rebooting again.

DarkLLord
11-20-02, 07:43 AM
If you want them enabled (I don't know whether just using these switched works) you would have to edit the os-registry.c file from the kernel packages

I did it that way and it works

brblueser
12-31-02, 01:47 PM
Hi folks,

I just tried both solutions (passing parameters to NVidia module and modifying NVIDIA_kernel source file os-registry.c) and none of them seem to work:


~ cat /proc/driver/nvidia/agp/status
Status: Enabled
Driver: NVIDIA
AGP Rate: 4x
Fast Writes: Disabled
SBA: Disabled


Any suggestions? Hardware supports both SBA and FW (according to manuals and SiSoft Sandra).

mobo: MSI-6380 K7T266 Pro2
graphics card: GeForce2 MX 400

TIA, and happy new year :)