Graphics card maker Nvidia is putting a stop to the resale of bundled promotional game keys by tying them to a specific graphics card purchase.

Previously, retailers sent promotional game codes to customers that purchased a qualifying product. Those codes could then be redeemed on Nvidia's website, which spit out the relevant Steam, Uplay, Origin, or Microsoft Store key. Since the promotional game codes were not tied to a specific account, many users took to either gifting spare keys to friends or selling them on eBay in order to offset the cost of the graphics card purchase.

Now, users have to redeem codes via the GeForce Experience (GFE) app, which is directly linked to third-party services like Steam and Uplay. Users must also ensure that the requisite graphics card is "installed before redemption." GFE then performs "a hardware verification step to ensure the coupon code is redeemed on the system with the qualifying GPU."

Update: Nvidia has confirmed that while GFE checks to ensure a user has installed a qualifying graphics card like a GTX 1070 or GTX 1080, the game itself is not permanently linked to the hardware. GFE's hardware check is based only on the wider product range, and not on a specific serial number.

The company has also confirmed that the redemption process permanently adds the game to the appropriate third-party service. For example, if users redeems a promotional game key through to Steam, that game will be useable on any other device, just like normal Steam games. Users can also opt to uninstall GFE, or install a different graphics card, once the promotional code has been redeemed and still retain full ownership of the game. A full set of instructions for redeeming codes is now available on Nvidia's website.

Ars is awaiting clarification on the status of codes for those that purchase two graphics cards for SLI.

The lockdown of promotional codes isn't an entirely unexpected move. Last year, Microsoft was forced to revoke codes for Gears of War 4 after an Amazon loophole allowed users to order a GTX 1070, receive the code, and then cancel the order. However, users are likely to be irked by the requirement to use GFE to redeem codes. The latest versions of GFE require users to register and login in order to use any of its functionality, which includes streaming games around the home, automatic settings optimisation, and automatic driver updates. Previous versions of GFE did not require a login.

"Login is what establishes the link between your system and the rest of the GeForce ecosystem," an Nvidia developer working on GFE said in a recent Nvidia forum post. "That's how we establish the connection that lets you stream from your PC to your Shield. That's how you redeem GeForce Experience rewards into your account. It's what lets you stream games from GeForce Now to your PC...To the conspiracy theorists, this has nothing to do with spying, tracking, or other nefarious activities."

Nvidia's new terms and conditions for promotional codes can be found in its latest bundle, which offers the choice of For Honor or Tom Clancy's Ghost Recon: Wildlands with the purchase of a GTX 1070 or GTX 1080.