[SOLVED] Increase screen resolution in Slackware 14.2

Hello,

Yesterday I installed Slackware 14.2 in Virtual Box. I installed everything that was recommended and the system seems to be running fine. The problem I'm having is I can't increase the screen resolution. I have a 27inch widescreen monitor with 1920 x 1080 resolution but I'm stuck at 1024 x 768. I tried "xorgconfig" so I could enter my monitor's specs manually but I got an error message saying the command was not found. When I ran "xrandr" it stated that it failed to get size of gamma for output default. I"m at a loss as to what to do next.

I'm new to Linux and Slackware. I chose Slackware because I like the DIY philosophy, and I want to learn. But a lot of the info I found online about fixing the screen resolution came with a warning that if done incorrectly there's a chance I could wreck my hardware. This is why I'm a little hesitant, and decided it best to ask a more experienced user for assistance.

Any help with this matter would be greatly appreciated.

Welcome to Slackware forum

You must install the Oracle extension pack to get higher resolutions, then reboot the vm.

Hi Paulo2, thank you for the welcome and your help

I just installed the Oracle extension pack as you said, but unfortunately I still can't change the screen resolution. I checked and it says it is installed and active. I also have the guest additions installed as well. Under storage it says the VBoxGuestAdditions.iso is on optical drive: IDE Secondary Master and attached to Slackware.

If not already done mount the VBoxGuestAdditions.iso as root in the VM and run the installer:

mount /dev/sr0 /mnt
sh /mnt/VBoxLinuxAdditions.run

It will take some time to build and install the modules.

Then you will be able to change the resolution from the VM's menu: Screen => Virtual Screen n°1

You will need to restart X in the VM or maybe to reboot it after that.

Did you reboot the vm?
I adjust a Debian vm with these commands.

cvt 1440 900
# 1440x900 59.89 Hz (CVT 1.30MA) hsync: 55.93 kHz; pclk: 106.50 MHz
Modeline "1440x900_60.00"  106.50  1440 1528 1672 1904  900 903 909 934 -hsync +vsync

xrandr 
Screen 0: minimum 320 x 200, current 1680 x 1050, maximum 16384 x 16384
DVI-I-1 disconnected (normal left inverted right x axis y axis)
DVI-D-1 connected 1680x1050+0+0 (normal left inverted right x axis y axis) 494mm x 320mm
...<etc>...

Run xrandr --newmode with the edited output of cvt and xrandr --addmode with the connected display.

xrandr --newmode "1440x900"  60.00 1440 1528 1672 1904  900 903 909 934 -Hsync +Vsync
xrandr --addmode DVI-D-1 "1440x900"

That resolution should appear as available.

Running

xrandr --output VGA-0 --mode "1440x900"

will set the new resolution.
I think this is safe with a virtual machine.

Hi Didier Spaier, thanks for the reply and your help. The solution worked, and I can now run my native screen resolution Paulo2, thanks again for your help as well