T30 Memory Cover

[kc27]

I've read about an alternate memory slot cover for T30s a few times on these forums - it is supposed to help prevent DIMM socket failure. How do you know if you have the updated memory slot cover? Is there an identifying mark or number?

[rkawakami]

The only identifying mark that I know of is that the updated memory cover is raised, while the "original" one is flat.

[jronald]

http://cgi.ebay.com/IBM-Thinkpad-T30-Me ... 1e5f127875

Look just inside the edge and you will see the raised portion.

Ron

[robert213]

More info here...
Sturdy DIMM Covers for T30
http://forum.thinkpads.com/viewtopic.php?f=28&t=78048

T30 - where to buy replacement cover plate?
http://forum.thinkpads.com/viewtopic.php?f=28&t=67744

[Norway Pad]

This is interesting. I hadn't heard about the memory socket failure before I read about it on the ThinkWiki page for the T30. I used a T30 for work from 2002 to 2007, but I was apparently one of the lucky ones that didn't experience this. But I have always thought the reason for the failure that's given on the ThinkWiki page is kind of funny:

The solder joint micro-fractures arise after a few years' use as the heavy and unsupported memory module sockets are located under the motherboard
. Exposing the laptop frequently to even minor shocks or vibration (e.g. placing the laptop daily onto a table or port replicator) will cause slow fatigue to the solder joints as the memory modules are basically hanging unsupported on the bottom side of the motherboard, and all vibration will cause them to move microscopically small amounts up and down. Eventually the fatigue of the solder joints will be creating a crack on one or more joints, being visible using a stereo microscope.

Is it really the weight of the "heavy and unsupported" module that is the reason? I never quite understood that. And can the minor shocks from handling the laptop cause so much vibration? If this can damage the sockets, I suspect it would also cause problems with other joints and BGA attached chips, and not just the memory sockets. I had my T30 mobo out last week, and if I am not wrong, the Northbridge chip is also "hanging" underneath the board.

However, the design of the improved cover sort of goes against this theory, because this cover actually creates more space underneath the socket/modules rather than being closer to them and supporting them. If vibration and weight was the reason, you would think that a thin layer of foam on the inside of the cover to support the modules would be the fix. So I am tempted to believe that the flat cover under certain conditions actually touches the sockets, and that the shocks and stress introduced by this can be a more likely reason than the "heavy" modules and vibrations. Especially if you put your fingers over the RAM cover while you grab and lift the laptop. Could it also be that the airflow and cooling is improved with the raised cover? Lower operating temperature means lower temperature differences and less stress introduced to the solder joints by the heating/cooling cycles.

Anyone know if there ever was an "official" reason for the failures coming from IBM? I will look into buying one of these if they are still available from the seller on eBay. (Edit: Found one today, so I'll see what this is in a couple of days)