The short answer is YES: RAM does indeed "age".
And some of the degradation is noticiable if you use it intensively (as servers do). However most non-server users won't notice it, which is why the usual answer is that RAM does not age. Which is incorrect.
The ageing mechanism(s) are quite complex, or at least are too involved to discuss here. And in any event, since you cannot really measure the degradation non-destructively, or even predict it very accurately, it doesn't help you very much to know the specific details.
So for the average user, if RAM failure is an issue, then about the only thing you copuld do is use new RAM, and replace it over time if you use it very heavily (as in a home server etc). After computer purchase, you normally don't get a choice of what RAM to use, in terms of type and ECC or not. Those are decided by the CPU/motherboard makers.
And as long as you recognise the signs of RAM failure, then replacing it is straightforward.
The ageing effects data retention time as well as other RAM aspects.
And its a function of:
- Number of erase cycles
- Temperature history
- Process size used to make RAM (as in the nm scale)
- Inherent defects in the RAM
In general, it's been found that all else being equal, as RAM cell size decreases, degradation rate increases (Study of Scaling Effects on DRAM Reliability
As well as here:
Thermal degradation of DRAM retention time: Characterization and improving techniques.
This is very good too:DRAM Reliability Aging Analysis and Reliability Prediction Model M.C.R.Fieback
It's quite hot topic.