Thanks for pointing me towards your post, this is the information I was looking for. I'm not that fussed about running this RAM at its rated speed, esp if it could result in instability and/or damage to the memory controller. These sticks are destined for a newer build in the not to distant future anyway.
You do seem to mention playing with the timings a little for RAM that is underclocked. Do you have any suggestions in this area? What timings have you been able to get away with, and with which parts? My current timings, as reported by CPU-Z are available in the image below. I understand if you'd rather reserve judgement on this matter.
Thanks for your help on this.