Keith,

We are using several PQ2FADS-VR and MPC8272ADS boards for a Linux project and are experiencing a high occurrence of boards that get into a state where they will not boot or behave erratically during boot.

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When folks bring me systems in this state, my "fix" has been to replace the 8MB flash SIMM. This usually gets them going again, but I honestly don't think the SIMM is the real problem. I have one PQ2FADS board that I have put four different SIMMs in and can not get it to boot. In most other cases, I can take the "bad" SIMM, put it in another board, reprogram it and it will work again (for a while).

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known good, tested kernels. Typically, users will have been working for weeks without a problem until they run into this.

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Any insight or shared experience on this is greatly appreciated.

From my experience a possible answer to your problem is that the contact

metal of the board connector does not match the metal of the contact area on your SIMMs. I saw similar problems before with self-built SDRAM SIMMs. The only way to get it working reliably was to use a board connector with gold plated contacts and to use a SIMM with a gold plated PCB. I am not a chemist or physicist but I think else the two different materials after a while build up some strange alloy / oxide that ruins the contact.

What's the plating of your board connector and what's the plating of the SIMM contact area?

Regards Mark