# XSF / General FAQ

Cyril Brulebois
`<kibi@debian.org>`

## Input drivers

- How do I configure input for X?
  Look at the how to configure input documentation.

- Why can’t I kill X through `Ctrl+Alt+Backspace`?
  That’s explained in the above-mentioned documentation.

## Video drivers

### All drivers

- What’s wrong with the DPI setting?
  By the default, the X server uses 96 DPI, as seen on upstream bug #23705 (in particular Keith’s comment). A particular DPI setting can be set through desktop environment’s preferences, through the `-dpi` X server command line option (see `Xserver`’s manual page), or through `xrandr`’s `--dpi` option.

- How do I get some info about 3D support?
  Look at the instructions to build mesa, there are a few commands to learn about 3D support, the current driver, etc.

### Ati driver

- Why is it I’m getting low performances, or even crashes?
  Make sure you have installed the `firmware-linux` package. The driver might still be working without the firmware, but using code paths which aren’t supported as well as the “normal” ones.

### Intel driver

- Why isn’t it working?
  KMS is mandatory, as documented in its `README.Debian` (view it online: salsa.debian.org). You probably disabled KMS or didn’t include it in your kernel configuration if you’re using a custom kernel.

- X is crashing all the time with my “old” Intel card. What can I do?
  Unfortunately, old cards are not very well supported, and you can’t do much more than switching to a generic driver, like `fbdev` or `vesa`, as documented in `README.Debian` (view it online: salsa.debian.org). Please note that you need to disable `KMS` if you want to use the `vesa` driver. A minimal `xorg.conf` would look like:

    Section "Device"
        Identifier "MyBuggyCard"
        Driver     "fbdev"
    EndSection

### Nouveau driver

- Why isn’t it working?
  Since it’s still considered experimental by its authors, the interfaces aren’t stable yet, so the driver has particular dependencies on the kernel, which are documented in `README.Debian` (view it online: salsa.debian.org).

## Others

### Session management

- How to start a bare X session (without Gnome, KDE, etc.)?
  Assuming there’s no X running on the `:1` display, run this from a VT:

    startx /usr/bin/xterm -- :1