Grand Theft Auto 5 players on Xbox 360 must install the first disc in order to play the game, but the second disc — the one you play off of — shouldn't be installed, said publisher Rockstar Games on Twitter today.

The Xbox 360 version of Grand Theft Auto 5 comes on two discs, and it requires players to install 8 GB of data to the console from the first disc. Once that initial installation is complete, that install disc is never used again; the game is played from the second disc. However, Rockstar warned against installing that disc, since doing so might affect performance.

"For optimal performance, we recommend not installing that disc," said Rockstar on the Rockstar Support Twitter account. "We will have more info on our Support Site at launch."

We've reached out to Rockstar for more details, and will update this article with any information we receive. In the meantime, you can read and watch our Grand Theft Auto 5 review here. The game will be available tomorrow, Sept. 17, on Xbox 360 and PlayStation 3.