If you look at gpu boss or gpu.userbenchmark, you will see that the 770 is the stronger card. However, the 1050 Ti has some advantages, such as double the VRAM, newer architecture and lower power usage. It really depends on the games your playing- if you are playing VRAM heavy games, like gta v, you'll get around 40fps at 1080p max, and with the 1050 Ti you'd get around 45. If you are playing games like Csgo, you'd get 10-20% better performance on the 770. However, it depends where you are getting these cards from. I picked up a 770 for £70 on eBay, and it was a premium twin Frozr one. Similar 1050 Ti is around £160, so I think the 770 is better value. It will last a good 3 years before it loses driver support, and after three years, you'll probably want to upgrade anyway. If you have £160, I'd save up for an RX 480 or GTX 1060. But if you just want to get a decent card for 1080p, the 770 should be fine.