Dell Latitude E5430 Black Screen After Changing Resolution

Questions: I have Dell Latitude E5430 Laptop. And it's black Screen after changing resolution. Here are is my dell latitude e5430 laptop specs:
Processor: 2nd gen Intel® Core™ i3-2350M Processor (2.3GHz, 3M cache)
Operating System: Windows 7 Professional, No Media, 64-bit, English
Display: 14.0" HD (1366x768) Anti Glare LED-backlit
Memory: 4GB2 DDR3 SDRAM at 1600MHz
Hard Drive: 500GB 7200rpm Hard Drive
Video Card: Express Card
Laptop Optical Drive: 8X DVD Drive for Dell Latitude E5430
Weight: 2.04 kg
Ubuntu 11.10 unrecognizes graphics and system info shows it as "Unknown". My external monitor ViewSonic VG730m is also listed as "Unknown". Maximum resolution i can take is 1024x768. Optimal resolution for monitor is 1280x1024. So i did this:

Dell Latitude E5530 DVD Drive, Dell Inspiron 17R SE 7720 DVD Drive, Dell Vostro 1450 DVD Drive

root@Latitude-E5430:~# xrandr Screen 0: minimum 320 x 200, current 1024 x 768, maximum 8192 x 8192 LVDS1 connected (normal left inverted right x axis y axis) 1600x900 60.0 + 40.0 1440x900 59.9 1360x768 59.8 60.0 1152x864 60.0 1024x768 60.0 800x600 60.3 56.2 640x480 59.9 VGA1 connected 1024x768+0+0 (normal left inverted right x axis y axis) 0mm x 0mm 1024x768 60.0* 800x600 60.3 56.2 848x480 60.0 640x480 59.9 HDMI1 disconnected (normal left inverted right x axis y axis) DP1 disconnected (normal left inverted right x axis y axis) HDMI2 disconnected (normal left inverted right x axis y axis) HDMI3 disconnected (normal left inverted right x axis y axis) DP2 disconnected (normal left inverted right x axis y axis) DP3 disconnected (normal left inverted right x axis y axis) root@Latitude-E5430:~# cvt 1280 1024 # 1280x1024 59.89 Hz (CVT 1.31M4) hsync: 63.67 kHz; pclk: 109.00 MHz Modeline "1280x1024_60.00" 109.00 1280 1368 1496 1712 1024 1027 1034 1063 -hsync +vsync root@Latitude-E5430:~# xrandr --newmode "1280x1024_60.00" 109.00 1280 1368 1496 1712 1024 1027 1034 1063 -hsync +vsync root@Latitude-E5430:~# xrandr --addmode VGA1 1280x1024_60.00 Now i can select 1280x1024 resolution in display settings, but after that i get black screen. Not "No signal", but black screen. What i should do?

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Answers: Alternative ideas:
1. Try editing the grub Menu script adding: "i915modeset=0" to the Linux boot line, & press 'Crtl+x'. If that does not work, try: "i915modeset=0 xforcevesa", or: "xforcevesa" on its own.
2. There are other things you could try in the same way, but it is rather clutching at straws, though editing out the 'quiet' and adding "verbose text" may give some clues as to what is going wrong, if the black screen is before login. eg. "acpi_osi=", acpi_osi=\"Linux\", or "vcmalloc=xxxM", { try '196' for 'xxx'}
See Post #1 in: http://ubuntuforums.org/showthread.php?t=1613132&page=9
3. Try booting via recovery to failsafe, low res.
4. Peruse the log files and .xsession-errors, in your home/user folder [Press 'Crtl+h' to show hidden files] Search for 'EE' & 'WW'. errors & warnings.
5+ etc, etc.....

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