The Same Youtuber ThirtyR attempted to play Far Cry 4 on 8k, and he actually succeeded by playing it on 60fps. The Gameplay was recorded and played by him, so all credit goes to him. The Youtuber has an awesome rig, must check it out.
On a serious note: Your PC may lag, so please consider checking your specifications first.
Video :

His Rig Specifications
Monitor: Dell UP3218K – 8K IPS Monitor
GPUs: 4x GTX TITAN Xp (2017) 4 WAY SLI @ 2038Mhz / 13358Mhz
MoBo: Asus Rampage V Extreme (X99)
CPU: i7 6950X @ 4.30GHz
RAM: Corsair Dominator Platinum DDR4 3200Mhz (64GB)
PSU: Corsair AX1500i
CASE: Cooler Master Cosmos II
OS: Samsung 850 Pro 256GB
Games/Programs: Samsung 840 EVO (RAID-0) / Samsung 850 EVO