Lol
1.100,- GBP is not a tight budget. Have you thought about building it yourself? It's not that hard and there are real good guides and forums on the net to help you out if you're not sure how to go about it. Buying the parts separately you can get more bang for your buck! I think roughly:
CPU: i7 6700 ~300,- GBP
GPU: Nvidia GTX 1070 ~370,-
Mainboard: ~130,-
RAM (16GB DDR4): ~100,-
Case: ~60,-
Power supply: ~60,-
HDD (2TB) ~60
DVD Writer: ~20,-
= ~ 1.100,-
Of course you will need a copy of windows which costs extra, so you might want to start out with only 8GB RAM (which is plenty!) to have some money left for the OS. The CPU comes with a cooler but if you want to exchange it for a quieter cooler you can always do that later. Also I'd recommend investing in a SSD at some point. But in my experience you don't feel the effect of a SSD in games, so it's not high priority.
In any case, look for this CPU/ GPU combo in offers for pre-built computers.
Cheers!