ubnutu設定設定螢幕分辨率

當然我知道ubnutu有圖形使用者界面可以設定分辨率，但是此文将的是自己手動設定。

ubuntu 9.04 did not detect the native resolution of my new lcd monitor which was 1440 x 900.

fix :

1. get the modeline for the required resolution + refresh rate using the gtf command.

<code>1</code>

<code>desktop:~$ gtf 1440 900 75</code>

<code>2</code>

<code>3</code>

<code>  </code><code># 1440x900 @ 75.00 hz (gtf) hsync: 70.50 khz; pclk: 136.49 mhz</code>

<code>4</code>

<code>  </code><code>modeline </code><code>"1440x900_75.00"</code>  <code>136.49  1440 1536 1688 1936  900 901 904940  -hsync +vsync</code>

the modeline is to be added to the xorg.conf file at /etc/x11/xorg.conf

take a backup of the file before editing it.

on a fresh ubuntu installation the file may look small like this :

<code>#some comments on top</code>

<code>section </code><code>"monitor"</code>

<code> </code><code>identifier </code><code>"configured monitor"</code>

<code>endsection</code>

<code>5</code>

<code>6</code>

<code>section </code><code>"screen"</code>

<code>7</code>

<code> </code><code>identifier </code><code>"default screen"</code>

<code>8</code>

<code> </code><code>monitor  </code><code>"configured monitor"</code>

<code>9</code>

<code> </code><code>device  </code><code>"configured video device"</code>

<code>10</code>

<code>11</code>

<code>12</code>

<code>section </code><code>"device"</code>

<code>13</code>

<code> </code><code>identifier </code><code>"configured video device"</code>

<code>14</code>

<code>15</code>

<code>16</code>

<code>section </code><code>"serverflags"</code>

<code>17</code>

<code> </code><code>option </code><code>"dontzap"</code> <code>"true"</code>

<code>18</code>

simply add the modeline to the monitor section like this :

<code> </code><code>modeline </code><code>"1440x900_75.00"</code>  <code>136.49  1440 1536 1688 1936  900 901 904 940  -hsync +vsync</code>

<code> </code><code>option          </code><code>"preferredmode"</code> <code>"1440x900_75.00"</code>

<code>19</code>

another fix could to be reconfigure x like : sudo dpkg-reconfigure xserver-xorg.

references :