Memory slot problem on a T23

[Zaph]

Hi!

I have this problem on my T23. When i do a boot of the system, about 80% of the time the 'front most' slot (the one that is nearest to me when i'm typing now) fails to notice the So-DIMM installed there. If i apply pressure to the memory slot cover about 3cm from the front and 10cm from the side of the laptop (about right next to the windows mirror logo sticker on the right side of it.) i get the memory noticed by the bootup diagnostics more often. If i don't apply the pressure i have to boot about 8 times before it works.

I'we brushed the slot with a dry toothbrush and very softly sanded the contactor on the So-dimm but the results stay the same. If i apply too much pressure the system won't boot at all and gives me a beep bessage that i'd hate to replicate.

Any ideas that might help this intermittent problem?

If the system fails to notice the sodimm, then it wont come up in windows or on any of the numerous HW diag softwares i'we used. It just doesent exist if it's not detected at boot time.

Memtest86+ runs perfectly if it get's noticed and doesent know there is a sodimm there if it doesent. I'we yet to manage an error on the memtest with warious pressures and knocking i'we applied to the sodimm while the tests were running.

I'we inserted a small piece of foam rubber in between the sodimm and the memoryslot cover and now only have to apply a very slight pressure to the cover and i'm usually up and running in 2-4 presses of the powerbutton.

Is this a know problem with T23? Is there anything i could do to make it better?

The 512mb sodimm i have in the other slot works every time, the original IBM 128mb sodimm is the one i have in the 'defective' slot.

Thankyou in advance for any and all help you could give me on this.

--Zaph T23 2647-4MG

[RealBlackStuff]

It is actually the T30 which sometimes has memory problems, I'm not (yet) aware of similar problems in a T23.
Have you tried swapping the memory sticks, i.e. put the 512 in front and the 128 in back?
Rather than foam rubber, try a piece of cardboard, or paper folded up enough times. You will need to experiment to get the proper thickness.
The cause is most likely a poor soldering contact in the memory slot.

By the way, don't use sanding paper, use an eraser (rubber or nylon) instead.

[rkawakami]

I (not "A" ) just recently had an experience with one of my T23 systems for a possible memory slot issue. The system is being used by my daughter's boyfriend and when I was updating the anti-virus program, I noticed it was running very slowly. I check the System Properties window and it said that it only had 512MB . I verified that there were TWO 512MB modules installed. Upon the next boot, Windows reported 1GB but again after a couple of re-boots, it stated 512MB again.

I pulled both modules out, cleaned the contacts, inserted them one at a time and received the 1-3-3-1 beep code indicating a memory problem. I also tried a couple of spare modules and it seemed like both slots were having problems. I re-installed the two original modules and shimmed them with folded pieces of paper between them and the memory cover and that appears to have (temporarily) fixed the problem. I'll be exchanging that system in a few weeks so I hope to get at the bottom of this.

[tfflivemb2]

I'll have to try shimming my T23 that is giving me the 1-3-3-1 error code. I tried several sticks, and can't believe that I didn't think about shimming them...I guess I was just too frustrated over fixing one problem and then having another one raise its ugly head...

[Zaph]

I'we tried different memory modules and the only common thing is that it's only the front slot that's giving the intermittent problem.

I'll have to take a magnifying glass to it and see if there is a bad solder somewhere.

I'll try and stack paper in between the foam rubber and the memory slot untill i get the right amount. I'we perfected the 'push the memory slot cover' technique to such a degree that i allmost allways get it right. Too little = i'm out of 128mb of memory, too much = beep code, gentle pressure = it notices the whole 640mb and all is good.

[skystyler]

I just recently had an experience with one of my T23 systems for a possible memory slot issue. The system is being used by my daughter's boyfriend and when I was updating the anti-virus program, I noticed it was running very slowly. I check the System Properties window and it said that it only had 512MB . I verified that there were TWO 512MB modules installed. Upon the next boot, Windows reported 1GB but again after a couple of re-boots, it stated 512MB again.

I pulled both modules out, cleaned the contacts, inserted them one at a time and received the 1-3-3-1 beep code indicating a memory problem. I also tried a couple of spare modules and it seemed like both slots were having problems. I re-installed the two original modules and shimmed them with folded pieces of paper between them and the memory cover and that appears to have (temporarily) fixed the problem. I'll be exchanging that system in a few weeks so I hope to get at the bottom of this.

I have exactly the same problem. I thought about creating shims out of paper, but the 2 x 512MB modules get very hot. I was worried about overheating, or worse starting a fire. should I be?

[rkawakami]

Welcome to thinkpads.com!

I don't believe that you would have any chance of igniting the paper that's touching the module(s). After all, most modules have paper stickers on them to begin with. Overheating may be an issue however. With paper being a fairly good insulator, extra heat build up might occur since there's reduced air circulation around the module. Ultimately the proper fix would be to re-flow the solder on the memory slot(s) or replace the motherboard.

Note: I corrected a typo that was in my posting from Sept. 2007. Don't know why I started out the first sentence with "A" instead of "I"