By default you’re unable to set a custom resolution in Ubuntu 13.10 while running on HyperV. This is how I set it up.

Modify the following file and make sure that you include the listed modules:

sudo vim /etc/initramfs-tools/modules

HyperV1

Update the initramfs:

sudo update-initramfs -u

Install the linux-image-extra-virtual package:

sudo apt-get install linux-image-extra-virtual

Update the GRUB_CMDLINE_LINUX_DEFAULT line in the GRUB file to reflect your desired screen resolution:

sudo vim /etc/default/grub

HyperV2

You can see that I changed from GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" to GRUB_CMDLINE_LINUX_DEFAULT="quiet splash video=hyperv_fb:1920x1080"

Update GRUB:

sudo update-grub

And now reboot and the changes should take effect :smile:

sudo reboot