fitted replacement board today ( not msi ) i5 now idle at 35c was running on old board idle at 75c under stress went over 100c now never gets above 50c conclusion not only can the flash on the MSI go wrong ( despite using their tools and bios from site ) The board was also an issue / fault ? fan was attached correctly / fresh paste so a bios upgrade was my only way forward alas we shall never know thanks to the MSI bad flash !!!