After Phyllome OS [has been successfully installed](/deploy/install) and [its first-launch process completed](/deploy/install#first-launch), a few tasks are required before it can be used to its fullest potential.
Any new user, including the one that has been created during the first-launch set up, won't be part of the `libvirt` group. It means that it won't be able to manage the *qemu:///system*, which runs `libvirt` as root.
To avoid a password prompt each time you connect to *qemu:///system*, you can add the current user to the `libvirt` by using the following command, in the terminal:
> Phyllome OS will eventually switch to the *qemu:///session* URI, which doesn't require elevated privileges. Have a look at [this great blog post](https://blog.wikichoon.com/2016/01/qemusystem-vs-qemusession.html) to understand some of the differences between the *session* and the *system* URI.
### Modify the system allocated to the GPU in the BIOS/UEFI (vfio-mdev only)
> Some computers allow you to modify the system memory allocated or shared with the integrated GPU, which may allow you to create more vGPUs.
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> For Intel integrated graphics cards only; rarely available on laptops computers.
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* Before the host operating system boots up, you need to enter the BIOS/UEFI and to look for a setting called *GPU aperture size*, or *GPU shared memory*.