For information on editing, see the description of Plan 9 wiki syntax.
If none of the monitors in /lib/vgadb fit your needs, you can create your own entry. Here, I'll go through the steps I used to make an entry for my Samsung SyncMaster 240T monitor. This assumes that you can boot Linux and get X running at a mode you like. I had mine running at 1920x1200 under X. Run xvidtune and collect the data it shows. Here's what I got: ! Vendor: SAMSUNG, Model: SYNCMASTER 240T(DIGITAL) ! Num hsync: 1, Num vsync: 1 ! hsync range 0: 29.00 - 81.00 ! vsync range 0: 39.00 - 85.00 ! HSyncStart: 2048 ! HSyncEnd: 2256 ! HTotal: 2592 ! VSyncStart: 1201 ! VSyncEnd: 1204 ! VTotal: 1242 ! Pixel clock: 193.15 MHz ! H-Sync: 74.52 kHz ! V-Sync: 60.00 Hz Using these values and the comments in vgadb, I came up with the following entry: ! sm240t=1920x1200 ! clock=193.15 ! shb=2048 ehb=2256 ht=2592 ! vrs=1201 vre=1204 vt=1242 Look at those numbers. You'll see that "clock" corresponds to the "pixel clock" value from xvidtune; shb, ehb and ht correspond to HSyncStart, HSyncEnd, and HTotal, respectively; vrs, vre and vt to VSyncStart, VSyncEnd, and VTotal. Once I had this entry added to /lib/vgadb, all that remained was to edit plan9.ini to say "monitor=sm240t" and "vgasize=1920x1200x32". This method should be applicable to most monitors.
