Thats a tall order for a 500 pound laptop I might be able to find something used if you want. You would be much better off buying a desktop if you want to game for 500 pounds, thats just not enough for a good gaming laptop CS GO would likely run fine but H1 Z1 is another story.
I think something like this is pretty good on a £500 (ish) budget.
Slightly over budget, mainly due to the GPU.
Intel chips are generally better than AMD in my experience and this one has good OC possibilities (I've had a 4690 up to 4.5GHz with an aftermarket cooler)
SSD should allow enough room for both an OS and a few games with good loading time.
8 GB 1866MHz RAM.
GPU should handle the games you mentioned and more (http/www.tomshardware.co.uk/asus-geforce-gtx-950-strix,review-33284.html)