I just installed Ubuntu 18.04 and 19.04 on my Dell Inspiron 17 3000 Series - 3793. Under Windows, the screen is well detected but not under Ubuntu... I upgraded the Ubuntu to see if the bug would be fixed without result. Here is the result of the xrandr command
$ xrandr
xrandr: Failed to get size of gamma for output default
Screen 0: minimum 1920 x 1080, current 1920 x 1080, maximum 1920 x 1080
default connected primary 1920x1080+0+0 0mm x 0mm
In the details of the PC, I have this : Carte graphique : llvmpipe (LLVM 8.0, 256 bits)
The secure boot is disabled for information.
Here are some of the commands I was able to execute :
$ cat /etc/default/grub | grep GRUB_CMDLINE_LINUX
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
GRUB_CMDLINE_LINUX=""
$ lsmod | egrep 'i915'
i915 1826816 0
drm_kms_helper 184320 1 i915
drm 487424 2 drm_kms_helper,i915
i2c_algo_bit 16384 1 i915
video 49152 3 dell_wmi,dell_laptop,i915
$ lspci -vnn | grep -A 12 '\''[030[02]\]' | grep -Ei "vga|3d|display|kernel"
00:02.0 VGA compatible controller [0300]: Intel Corporation Device [8086:8a52] (rev 07) (prog-if 00 [VGA controller])
Kernel modules: i915
$ uname -r
5.0.0-35-generic
$ lspci -nnk | egrep -iA3 "VGA"
00:02.0 VGA compatible controller [0300]: Intel Corporation Device [8086:8a52] (rev 07)
Subsystem: Dell Device [1028:097a]
Kernel modules: i915
00:04.0 Signal processing controller [1180]: Intel Corporation Device [8086:8a03] (rev 03)
Thank you in advance for your precious help !!