Thanks chap
That's interesting to know, that was my kind of idea too, go for a stop gap CPU and 450 board that (should) accept zen2. Was originally thinking 1700 but just been looking at 1600x, they are in the £120 region!!!
To be honest I could have held out a while longer but after purchasing the Vega I wanted a nice case. I didn't want to have to move everything now and then redo it all in 6 months so took the jump now, I don't mind about missing out on PCIE 4