Micron SDRAM memory chips manufactured between 2005 and 2010 degrade over time

[bernroth]

Hello folks!

I think the forum is the best place to put that information.

There are many Micron memory chips out there which degrade over time.
These chips have been manufactured between 2005 and 2010 (according to Cisco).

Here is a dedicated webpage from Cisco:

https://www.cisco.com/go/memory

They do not blame Micron but I had many of the affected Cisco products on my bench for repair 

After replacing the broken Micron memory chips, all was back to normal.

I am convinced that not only Cisco is affected.
Possibly there are other field notices from other manufacturers out there.

Would be great to collect them here.
Links & comments are welcome!

Best regards,
Bernhard

[pinkman]

This is really interesting.  Can you post particular part numbers of affected memory you have replaced?  Is this DRAM?  I wonder if the little dram caps are just becoming more leaky and discharging before the refresh, and if so, what the root cause is.  This sounds like network equipment, and is probably powered on continuously, maybe even an electromigration issue? 

It seems that the time period in question was during the initial dramatic increase in memory density, maybe things moved too quickly and some lessons were not learned yet.

[bernroth]

The chips I'm replacing in failed Cisco network equipment are Micron 46V32M16-6T

There might be many other model numbers affected but the industry is keeping silent.
Unlike software security problems, issues with components are still not very public.

I was unable to find a comprehensive list of affected products/chips form the manufacturer.

[Jeroen3]

This is known since 2015?

[bernroth]

Cisco usually publishes informations quite quick (see Intel Atom C2000 series LPC clock failure).
So yes, possibly known since 2015.


Edit: As long as the device is running, it works fine.
The problem is when you power-cycle it, the memory stops working.


Anyone with more informations?

A Micron field notice for manufacturers would be nice.