AMD and Ubisoft have partnered to gift Far Cry 5 to gamers who purchase a select prebuilt PC. Qualifying systems must have a Radeon RX Vega 64, Radeon RX Vega 56, or Radeon RX 580 graphics card inside and come from a specific list of vendors, of which there are several.
In the US, system builders participating in the program include AVA Direct, CyberPower PC, Cybertron PC, Digital Storm, Extreme PC, Falcon Northwest, iBuyPower, Maingear, Origin PC, Puget Systems, Velocity Micro, Xidax, and Xotic. There are several more in the EMEA region and other territories that are participating as well.
Free game incentives are not unusual, though in what's become an unfortunate sign of the current times, the promotion only applies to prebuilt PCs and not standalone graphics cards. While not stated, this seems to be an acknowledgement that the demand created by cryptocurrency mining has caused a shortage of standalone cards, which are incredibly difficult to find in stock and at a fair price. That's not the case with system builders, however, hence why AMD can run a promotion like this.
How it works is after you purchase a qualifying system, you'll receive a coupon code for Far Cry that you can redeem at AMD's rewards site for your Uplay library. The promotion is in effect now and runs through May 20, 2018, and you have until July 15 to claim your copy. Just bear in mind that you'll have to wait until the game releases on March 27 to actually play it.
If you're interested in this offer, be sure to read through the fine print (PDF).