Found the answer... Unlike my old card, the new one has pre-set min/max range on the GPU and memory for over-clocking. So the Catalyst Control centre no longer needs to test in this range for stability problems. Although, it is advised to keep below 95%.
Above that, the likes of MSI afterburner are required with the safeties disengaged. And in my case (which I am doing) add additional cooling.
(Cacher) Vous n'arrêtez pas de perdre au temps? Les abonnés peuvent activer les Vacances Automatiques pour mettre un jour de vacance lorsquils risquent de perdrent au temps. (pauloaguia) (Montrer toutes les astuces)