Something similar happened a few years back with the Atom CPUs. The downside is that these were typically found soldered on expensive devices like Cisco routers, firewalls, etc. The company I was working at the time had to RMA a ton of devices that could be faulty. I thought for sure that this would result in earnings hits and lawsuits but none of that seemed to happen.
Avotons keep degrading even if you do the resistor mod to temporarily get the clock signal back within range. I had a repaired one die again a few years afterward.
I bet they all are bad. Intel just hopes failure rate is low enough to RMA instead of recall.
> How do owners of that series of CPU, who suspect theirs is one of the defective units, exchange it for a non-defective CPU before it fails?
Another bet: class action suits.