Wait for Assassin's Creed Odyssey PC Specs
If you're currently using an older PC computer, you should avoid a pre-order and wait for Ubisoft to reveal the minimum and recommended spec requirements.
For the moment, Assassin's Creed Odyssey pre-orders don't include the minimum or recommended specs for Windows PC. The company didn't confirm them on stage during E3 either.
Typically, this information is revealed much closer to launch after development is finished up.
If you own a newer, high-powered computer, you should be good to go. However, if your setup is several years old, you might need to make some upgrades in order to get a great experience out of the next Assassin's Creed game.
If you can't or simply don't want to upgrade your PC right now, hold off on a pre-order until you can see how well the game will perform on a computer similar to yours.