# How to Swap Machines Attached to Notebooks

Notebooks are a web-based Jupyter IDE with shared persistent storage for long-term development and inter-notebook collaboration, backed by accelerated compute.

You can swap out a machine for a different machine at any time using notebooks when deciding what machine to select.

## Swapping Machines in an Existing Notebook

To swap instances in an existing notebook, use the **Instance** selector on the left side of the notebook. If the notebook is in the **Running** state, you first need to stop the instance.

![Notebook page showing stopping the instance.](https://docs.digitalocean.com/screenshots/paperspace/stop-machine.d208597b3cd9fca2f7cff932da0840a048c9d531ef3c319738c7165c2cc4a3ad.gif)

After the instance is stopped, you can select a new instance from the list of available machines.

The top bar indicates when a notebook is in the **Running** state.

## Unavailable Machines

If an instance type is at capacity it is listed as “Unavailable”.

If the machine type is listed as unavailable, you need to wait until capacity frees up. You can check if the machine type is available after waiting for a few minutes then refreshing the page. If its capacity is still not available, you could try a different instance with better availability or return to that instance on a less busy time of the day.

**Note**: Free GPU instances are often in high demand. You could try using popular free resources outside of peak hours which are from MF 9:00 AM - 5:00 PM ET, or try using more powerful paid machines.

Paperspace constantly adds capacity to its datacenters, so you should check the [Changelog](https://updates.paperspace.com) about capacity upgrades.

## Machine Auto-shutdown

The auto-shutdown timer automatically shuts down a notebook after a pre-determined amount of time. The timer starts from the moment that the notebook is started.

![Select a machine section showing machine selection, GPU type, auto-shutdown timer, and public access toggle.](https://docs.digitalocean.com/screenshots/paperspace/autoshutdown-timer.6bb220789c68cf12414239372ecb17bfc7797187a90640862dbdf4958784ffe8.gif)

When a notebook is running, the amount of time remaining until auto-shutdown is displayed in the **Instance** tab.

It is currently not possible to alter the auto-shutdown interval of a running notebook after it has been set.