Dash clocks resetting?

[Niall]

Dont discount a new battery. We use ACT gold testers at work which are much more advanced than that one you have there and even the manufacturer basically says use your instinct. They only simulate load on the battery.
I would however be looking at checking cabling. I replaced my battery earth loom as it was very frayed and corroded. I was genuinely shocked as to how much better everything worked and before hand it didnt even seem that bad!