i have no idea what modes to configure. when trying to xf86config with
minimal 640x480 with SVGA server i've got that below and screwed vision
when trying to do some modes manually machine locked up completely.
it is toshiba T4850CT (486/66 or maybe 80).

thank you!

XFree86 Version 3.3.6 / X Window System
(protocol Version 11, revision 0, vendor release 6300)
Release Date: December 20 1999
	If the server is older than 6-12 months, or if your card is newer
	than the above date, look for a newer version before reporting
	problems.  (see http://www.XFree86.Org/FAQ)
Operating System: NetBSD/i386 1.5 [ELF] The NetBSD Foundation, Inc.
Configured drivers:
  SVGA: server for SVGA graphics adaptors (Patchlevel 1):
      NV1, STG2000, RIVA 128, RIVA TNT, RIVA TNT2, RIVA ULTRA TNT2,
      RIVA VANTA, RIVA ULTRA VANTA, RIVA INTEGRATED, GeForce 256,
      GeForce DDR, Quadro, ET4000, ET4000W32, ET4000W32i, ET4000W32i_rev_b,
      ET4000W32i_rev_c, ET4000W32p, ET4000W32p_rev_a, ET4000W32p_rev_b,
      ET4000W32p_rev_c, ET4000W32p_rev_d, ET6000, ET6100, et3000, pvga1,
      wd90c00, wd90c10, wd90c30, wd90c24, wd90c31, wd90c33, gvga, r128, ati,
      sis86c201, sis86c202, sis86c205, sis86c215, sis86c225, sis5597,
      sis5598, sis6326, sis530, sis620, sis300, sis630, sis540, tvga8200lx,
      tvga8800cs, tvga8900b, tvga8900c, tvga8900cl, tvga8900d, tvga9000,
      tvga9000i, tvga9100b, tvga9200cxr, tgui9400cxi, tgui9420, tgui9420dgi,
      tgui9430dgi, tgui9440agi, cyber9320, tgui9660, tgui9680, tgui9682,
      tgui9685, cyber9382, cyber9385, cyber9388, cyber9397, cyber9520,
      cyber9525, 3dimage975, 3dimage985, cyber9397dvd, blade3d, cyberblade,
      clgd5420, clgd5422, clgd5424, clgd5426, clgd5428, clgd5429, clgd5430,
      clgd5434, clgd5436, clgd5446, clgd5480, clgd5462, clgd5464, clgd5465,
      clgd6205, clgd6215, clgd6225, clgd6235, clgd7541, clgd7542, clgd7543,
      clgd7548, clgd7555, clgd7556, ncr77c22, ncr77c22e, cpq_avga, mga2064w,
      mga1064sg, mga2164w, mga2164w AGP, mgag200, mgag100, mgag400, oti067,
      oti077, oti087, oti037c, al2101, ali2228, ali2301, ali2302, ali2308,
      ali2401, cl6410, cl6412, cl6420, cl6440, video7, ark1000vl, ark1000pv,
      ark2000pv, ark2000mt, mx, realtek, s3_virge, AP6422, AT24, AT3D,
      s3_savage, s3_svga, NM2070, NM2090, NM2093, NM2097, NM2160, NM2200,
      ct65520, ct65525, ct65530, ct65535, ct65540, ct65545, ct65546,
      ct65548, ct65550, ct65554, ct65555, ct68554, ct69000, ct64200,
      ct64300, mediagx, V1000, V2100, V2200, p9100, spc8110, i740, i740_pci,
      Voodoo Banshee, Voodoo3, smi, generic
Using pcvt driver (version 3.32)
XF86Config: /etc/XF86Config
(**) stands for supplied, (--) stands for probed/default values
(**) XKB: disabled
(**) XKB: keymap: "xfree86(us)" (overrides other XKB settings)
(**) Mouse: type: Microsoft, device: /dev/mouse, baudrate: 1200
(**) Mouse: buttons: 3
(**) SVGA: Graphics device ID: "My Video Card"
(**) SVGA: Monitor ID: "My Monitor"
(--) SVGA: Mode "800x600" needs hsync freq of 35.16 kHz. Deleted.
(--) SVGA: Mode "1024x768" needs hsync freq of 35.52 kHz. Deleted.
(--) SVGA: Mode "640x400" needs hsync freq of 37.86 kHz. Deleted.
(--) SVGA: Mode "640x480" needs hsync freq of 36.46 kHz. Deleted.
(--) SVGA: Mode "640x480" needs hsync freq of 37.50 kHz. Deleted.
(--) SVGA: Mode "800x600" needs hsync freq of 37.88 kHz. Deleted.
(--) SVGA: Mode "640x480" needs hsync freq of 43.27 kHz. Deleted.
(--) SVGA: Mode "1152x864" needs hsync freq of 43.92 kHz. Deleted.
(--) SVGA: Mode "800x600" needs hsync freq of 48.08 kHz. Deleted.
(--) SVGA: Mode "1024x768" needs hsync freq of 48.36 kHz. Deleted.
(--) SVGA: Mode "640x480" needs hsync freq of 53.01 kHz. Deleted.
(--) SVGA: Mode "1152x864" needs hsync freq of 53.51 kHz. Deleted.
(--) SVGA: Mode "800x600" needs hsync freq of 55.84 kHz. Deleted.
(--) SVGA: Mode "1024x768" needs hsync freq of 56.48 kHz. Deleted.
(--) SVGA: Mode "1280x1024" needs hsync freq of 51.02 kHz. Deleted.
(--) SVGA: Mode "800x600" needs hsync freq of 64.02 kHz. Deleted.
(--) SVGA: Mode "1024x768" needs hsync freq of 62.50 kHz. Deleted.
(--) SVGA: Mode "1152x864" needs hsync freq of 62.42 kHz. Deleted.
(--) SVGA: Mode "1280x1024" needs hsync freq of 64.25 kHz. Deleted.
(--) SVGA: Mode "1024x768" needs hsync freq of 70.24 kHz. Deleted.
(--) SVGA: Mode "1152x864" needs hsync freq of 70.88 kHz. Deleted.
(--) SVGA: Mode "1280x1024" needs hsync freq of 74.59 kHz. Deleted.
(--) SVGA: Mode "1600x1200" needs hsync freq of 75.00 kHz. Deleted.
(--) SVGA: Mode "1152x864" needs hsync freq of 76.01 kHz. Deleted.
(--) SVGA: Mode "1280x1024" needs hsync freq of 78.86 kHz. Deleted.
(--) SVGA: Mode "1024x768" needs hsync freq of 80.21 kHz. Deleted.
(--) SVGA: Mode "1280x1024" needs hsync freq of 81.13 kHz. Deleted.
(--) SVGA: Mode "1600x1200" needs hsync freq of 87.50 kHz. Deleted.
(--) SVGA: Mode "1152x864" needs hsync freq of 89.62 kHz. Deleted.
(--) SVGA: Mode "1280x1024" needs hsync freq of 91.15 kHz. Deleted.
(--) SVGA: Mode "1600x1200" needs hsync freq of 93.75 kHz. Deleted.
(--) SVGA: Mode "1600x1200" needs hsync freq of 105.77 kHz. Deleted.
(--) SVGA: Mode "1280x1024" needs hsync freq of 107.16 kHz. Deleted.
(--) SVGA: Mode "1800X1440" needs hsync freq of 96.15 kHz. Deleted.
(--) SVGA: Mode "1800X1440" needs hsync freq of 104.52 kHz. Deleted.
(--) SVGA: Mode "512x384" needs vert refresh rate of 77.97 Hz. Deleted.
(--) SVGA: Mode "512x384" needs hsync freq of 34.38 kHz. Deleted.
(--) SVGA: Mode "320x240" needs hsync freq of 39.38 kHz. Deleted.
(--) SVGA: Mode "400x300" needs hsync freq of 35.16 kHz. Deleted.
(--) SVGA: Mode "400x300" needs hsync freq of 37.88 kHz. Deleted.
(--) SVGA: Mode "400x300" needs hsync freq of 48.08 kHz. Deleted.
(--) SVGA: Mode "480x300" needs hsync freq of 35.16 kHz. Deleted.
(--) SVGA: Mode "480x300" needs hsync freq of 37.80 kHz. Deleted.
(--) SVGA: Mode "480x300" needs hsync freq of 39.56 kHz. Deleted.
(--) SVGA: Mode "480x300" needs hsync freq of 48.00 kHz. Deleted.
(**) FontPath set to "/usr/X11R6/lib/X11/fonts/local/,/usr/X11R6/lib/X11/fonts/misc/,/usr/X11R6/lib/X11/fonts/75dpi/:unscaled,/usr/X11R6/lib/X11/fonts/100dpi/:unscaled,/usr/X11R6/lib/X11/fonts/Type1/,/usr/X11R6/lib/X11/fonts/Speedo/,/usr/X11R6/lib/X11/fonts/75dpi/,/usr/X11R6/lib/X11/fonts/100dpi/"
(--) SVGA: WD: Signature for WD90C[23]X=[0x32 0x34]
(--) SVGA: WD: Detected 90C24.  Try 90C30 or 90C31 if this doesn't work.
(--) SVGA: WD: Current clock is 0x5
(--) SVGA: chipset:  wd90c24
(--) SVGA: videoram: 1024k
(--) SVGA: clocks:  28.32  28.32  28.32  28.32  28.32  28.32  28.32  28.32
(--) SVGA: clocks:  28.32  28.32  28.32  28.32  28.32  28.32  28.32  28.32
(--) SVGA: clocks:  20.17
(**) SVGA: Using 8 bpp, Depth 8, Color weight: 666
(--) SVGA: Maximum allowed dot-clock: 90.000 MHz
(--) SVGA: There is no defined dot-clock matching mode "640x480"
(--) SVGA: Removing mode "640x480" from list of valid modes.
(--) SVGA: There is no mode definition named "800x600"
(--) SVGA: Removing mode "800x600" from list of valid modes.
(--) SVGA: There is no mode definition named "1024x768"

Fatal server error:
No valid modes found.


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