Apologies, I should have reported back earlier than this but life got in the way.
I tried the other set of ram and there were no issues with that either.
However, things did get worse, random crashes when both gaming and just browsing, all sorts of errors in event log.
So I decided to reinstall windows from scratch and log everything as I went.
I experienced muliple crashes during the windows installation.
After it finally managed to complete there were further crashes / errors when downloading / installing programs.
Just as an example, I downloaded chrome browser and it refused to install, downloaded again, refused again, downloaded again, refused again.
All 3 downloads were the same size, after a number of attempts it decided to install from the first dl.
This happened with a number of different programs.
The random crashing and programs shutting down continued.
To try and cut an already long story short I contacted overclockers customer services.
I explained all of the above and the history already outlined in this thread and after a couple of questions answered I received an RMA.
I sent the CPU back on a Monday afternoon and received a replacement on Wednesday afternoon.
All seems well with this one so I guess the answer to the thread title was yes.
Also, thanks to OC's for excellent after sales support much appreciated.