The selected answer should be quoted beneath the OP, it is in my browser. Otherwise it is here.
It isnt really an answer, more the summary of how far I was able to get with the advice of others including my retailers after all the testing and replacing the CPU. I thought by selecting it as the answer it would make it easier for people with similar problems to get to the relevant facts quicker rather than read the whole thread through.
I did not intend selecting a correct answer to close down the discussion. I have found it very interesting to read what people have added to the thread and hope we can get some advice from Intel engineers about questions raised by other contributors, I understood these had been passed on to a different BB so I hope answers will still be forthcoming, as looking around the net at other tech BBs there are a lot of people struggling with this problem of overheating 4790Ks and all could do with some direction.
The impression I am getting is that the I7 haswells are hot CPUs. With my case closed up and a couple of more powerful outflow case fans 140mm120mm added my replacement has been running at mid 70's in games with 44x4 turbo and I have had to bring it down to 41x4, 42x3, 43x2, 44x1 to keep temps in the 60s (ie below Tcase 72.72°C) with a Noctua NH-L12. To get it to run 4 cores at 4.4GHz turbo I would have to get a much better cooler. Unfortunately the case I have is too small and was designed for air before hydro AIOs bcame so popular, so all the fans are in the wrong places for rads. I could get a new case only it is a gift from family so it has sentimental value so I will accept the reduction in top turbo speed for that reason. My other option is to delid it and sort out the TIM thickness but I really dont feel like it at the moment having just put it all together.