QualitySettings.vSyncCount

Description

The VSync Count.

The number of VSyncs that should pass between each frame. Use 'Don't Sync' (0) to not wait for VSync. Value must be 0, 1 or 2.

Windows Store Apps: It's not possible to disable VSync when DirectX 11 is used due to platform limitations, you can disable VSync if DirectX 12 is used.

using UnityEngine;
using System.Collections;

public class ExampleClass : MonoBehaviour {
    void Example() {
        QualitySettings.vSyncCount = 1;
    }
}

See Also: Quality Settings.