Going above 2133Mhz with regards to northbridge

An APU user looking to overclock their memory to 2400Mhz~effective can easily do so with XMP/AMP. But does the APU northbridge also need to be overclocked in order to make use of that extra bandwidth. I need someone more experienced in overclocking to clarify this. Thanks.

for AMD some gains are seen by upping the north bridge. i think anything over 2400-2500 is over kill and more hassle than its worth most of the time.

Yes, but is it necessary? Does anything else need to be overclocked in order for >2133 memory to be effective?

Others have claimed northbridge at stock speeds to be a bottleneck to fast memory and I'm just looking for confirmation or denial.

if you are benching yes if you are doing anything other than gaming maybe. but for gaming it is minimal if any gains.