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Valve is testing an option in the new Steam client beta that will force games by default to only download updates when you launch them.
Currently, Steam by default decides what game updates to download based on a few different things. As explained by Valve:
For games you recently played, Steam will download game updates shortly after they are released. For games that you haven’t played in a while, Steam might wait a few days to bundle multiple updates together or choose to download the update while you are asleep.
This new default option to wait to download an update gives players more control; as Valve points out, it means that users can hold an updating a massive game until they actually want to play it, which could be a relief for people with bandwidth caps.
You’ll find the new option in the beta Steam client settings under the Downloads section. “You can set the default to: let Steam decide when to update the game (based on factors like when you last played the game, bandwidth availability, etc.) or wait to update until the game is launched,” Valve says.
You can still set per-game download settings in a game’s Properties that override the global setting, but those options have “cleaned up descriptions,” according to Valve. And with the beta, you can also manage the per-game overrides in the overall Steam client Downloads settings.
Image: Valve