I had 17.04 on my Dell Latitude E5500 and all was well but it was out of support. So I upgraded in stages and when I got to 18 I noticed that I lost my display after the reboot. My external monitor and laptop display would come to life and then the external would loose the input signal. On the laptop the screen was dark with some mouse flicker. So I unplugged the external VGA cable and the laptop display came back. After a few more reboots the external display still would not work. If I plug it in the laptop display goes out and the display keeps trying to start up and then looses signal. I then upgraded to 19 with the same issue still present. I then went to 20.04 and all is well but the display issue remains.

This is just a plain old laptop. No gaming or high end graphics needed on this machine. Just email and web.

I ran a couple of commands from other video display issue posts and here is the output. I would appreciate any advice.

Mobile Intel® GM45 Express Chipset (CTG)
Screen 0: minimum 320 x 200, current 1280 x 800, maximum 8192 x 8192
LVDS-1 connected primary 1280x800+0+0 (normal left inverted right x axis y axis) 330mm x 210mm
1280x800 59.98 + 59.97 59.81 59.91 40.00*
1280x720 60.00 59.99 59.86 59.74
1024x768 60.04 60.00
960x720 60.00
928x696 60.05
896x672 60.01
1024x576 59.95 59.96 59.90 59.82
960x600 59.93 60.00
960x540 59.96 59.99 59.63 59.82
800x600 60.00 60.32 56.25
840x525 60.01 59.88
864x486 59.92 59.57
800x512 60.17
700x525 59.98
800x450 59.95 59.82
640x512 60.02
720x450 59.89
700x450 59.96 59.88
640x480 60.00 59.94
720x405 59.51 58.99
684x384 59.88 59.85
680x384 59.80 59.96
640x400 59.88 59.98
576x432 60.06
640x360 59.86 59.83 59.84 59.32
512x384 60.00
512x288 60.00 59.92
480x270 59.63 59.82
400x300 60.32 56.34
432x243 59.92 59.57
320x240 60.05
360x202 59.51 59.13
320x180 59.84 59.32
VGA-1 disconnected (normal left inverted right x axis y axis)
HDMI-1 disconnected (normal left inverted right x axis y axis)
DP-1 disconnected (normal left inverted right x axis y axis)
HDMI-2 disconnected (normal left inverted right x axis y axis)
DP-2 disconnected (normal left inverted right x axis y axis)
DP-3 disconnected (normal left inverted right x axis y axis)
SVIDEO-1 disconnected (normal left inverted right x axis y axis)

lspci -k | grep -A 2 -i "vga"
00:02.0 VGA compatible controller: Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller (rev 07)
Subsystem: Dell Mobile 4 Series Chipset Integrated Graphics Controller
Kernel driver in use: i915