This is inaccurate. Since "G-Sync Compatible" is just Nvidia's branding for FreeSync displays that have been certified to meet their arbitrary standards for G-Sync, it means that any graphics card with support for adaptive sync should support the feature equally well on these screens. That goes for all of AMD's recent graphics cards, and likely Intel's as well once they join the market next year, along with the Xbox One and almost certainly next year's new consoles from Microsoft and Sony. In fact, I believe these screens already featured FreeSync support, so not much has really changed, aside from Nvidia finally adding support for Adaptive Sync over HDMI with their latest drivers. On LG's end, their firmware update likely just makes some minor changes, like having adaptive sync enabled by default, which Nvidia requires for certification, and maybe using Nvidia's branding to refer to it.Of course, in order to enjoy the screen tear fighting benefits of G-Sync Compatibility, you'll need to connect one of these TVs to a gaming PC running an Nvidia graphics card.
If you don’t own a LG TV, but do own a display or TV that only supports Variable Refresh Rates via HDMI, you can try enabling HDMI VRR by installing the new Game Ready Driver, and enabling G-SYNC as detailed above. As these displays and TVs have yet to through our comprehensive validation process, we can’t guarantee VRR will work, or work without issue.