I am going to buy one in a few weeks. That or the LG 34GK950G.
The 980Ti will drive it, but you are in trouble with some modern titles. It's going to struggle with things like Monster Hunter, and barely manage 50fps. You need at least a 2070 Super to get it to 60fps for a modern title like Monster Hunter and eventually a 3080 or better to get it to a confident 100fps. 100Hz is effectively the limit of these monitors, thanks to the G-Sync module which is rated at 100Hz for 3440x1440. If you play older games then a 3070 will be more than good enough. But if you are spending £1000 on a monitor I assume you will be able to afford a 3080 when they come out!!