Memory slot"DIMM0" problem in TP 600X

[Bernt]

I have recently had some memory related chrashes on my TP 600X. Eventually, I found out that there where something called memory tests, and now I have tried Windows Memory Diagnostic on my system.

The original (64MB) memory module in slot "DIMM0" fails the test, but my two extensions (64MB in slot1, and 126MB in slot2) seem to be alright. So, naturally, my question is: what can I do about [i]this[/i].?

I know how to replace units in slot1, and slot2, but slot0 lies beneath these, how can it be accessed? I happen to have a spare 64MB module, and would, off course, want to replace the faulty one with this, but how? I don't even know if the original units, and the FRUs that are added later are of exactly the same kind.

[JHEM]

The 64MB of RAM on the MB is soldered in place, it's not in a socket.

Can't be changed.

What specific fault report leads you to suspect the onboard RAM is flakey? This would be VERY rare!

What are the exact specs on the memory you've added?

Regards,

James

[Bernt]

What specific fault report leads you to suspect the onboard RAM is flakey? This would be VERY rare!

What are the exact specs on the memory you've added?

Thank you for your answer, some background and specifikations:

The reasons why I think there may be something wrong with my memory are

(1) When working with footnotes in WP9, I have on some occasions experienced a chrash. I interpreted it as a sign of a too small memory (XP Pro), so I extended it form 192MB to 256MB. Haven't had this problem since, but haven't actually been working with many footnotes either.

(2) But now, with 256MB, I have problems with a language learning program. It frequently crashes, windows gives me one of its cryptical explanations: "The instruction at '0x7c910f29" reference memory at '0x00000000', the memory could not be 'read'".

(3) So today I tried Windows Memory Diagnostics on my system. When I run the test, and choose the option "View errors by memory module", I get the answer:

Windows MD found 105 errors. The error distribution is:

Bank Bank 0/3 Slot Dimm0 105
Bank Bank 1/4 Slot Dimm1 0
Bank Bank 2/5 Slot Dimm2 0

This is my reason for thinking there is something wrong with the preinstalled memory. But, I also ran a IBM PC-doctor test on the system, and guess what? No failures where identified!

Are there more reliable memory tests around?

Specs of the added memory:

Apacer 64MB PC 100, P/N 71.62 461.112, S/N 2000163-00754
IBM 128 MB PC 100 FRU 20L0265


Regards,

Bernt

[tfflivemb2]

Since the onboard ram is soldered, you can always try to add more ram via DIMM1 and DIMM2, and disable the onboard ram, to avoid the problems. I believe that the instruction on how to disable the onboard ram via a BIOS hack are available in the 600 upgrade sticky at the top of this conference.

This would also allow you to temporarily disable it and see if it is infact your problem.

[JHEM]

Were I you I'd pull that stick of Apacer memory, they rarely play nicely with other brands.

Nor can I find that part number on the Apacer website. I suspect that it's really PC133 memory relabelled as PC100, an all too common problem with "off brand" memory.

Try to find some IBM part no. 33L3070 PC100 256MB memory on eBay and max your 600X out. Should resolve any memory problems you're seeing.

Regards,

James

[Bernt]

One question about memory modules of 600X. Are they right- and left-handed, so to say? What I mean is, whether it is possible to move a module from the right side to the left, and the other way around? As far as I can see it would involve turning the module upside down, and I wonder wheter it works. In other word, does the label always have to be up?

The thing that confuses me, is that there never seems to be any mention anywhere of which side the module is for (assuming I am right). So, one could easily buy to modules for the right side, or two for the left??

[JHEM]

No, memory modules aren't "handed" and you can't put them in wrong way round.

The cutout in the module's connector strip is the only thing one need worry about when installing memory and that's there to prevent putting memory in the wrong way.

So, unless you're installing memory with a hammer, you can't put it in wrong.

Regards,

James

[warwound]

I tried the Microsoft Memory Diagnostic tool once and it reported many errors on my 600E...

I found from a search of this forum that the MS Memory Diagnostic tool has maybe compatibility problems with Thinkpads and that it's error reports may not actually be accurate.

Take a look at this thread.

warwound.

[rkawakami]

Hopefully this post is not too late, but it should contain some useful information for this kind of problem.

Another memory test program that's been around for some time now is "memtest86+". It is an updated version of the original "memtest86" and can be found at:

http://www.memtest.org/

I have been using this program for my personal 600X laptops for about a year now and am quite pleased on how it works. I work as a memory test engineer for a company that used to design and manufacture DRAM. The applications group at work uses memtest86+ to debug problems with various memory modules in all sorts of motherboards.

This program resides on floppy disk (remember those?) so you will need to put the floppy drive in the Ultrabay or use the external floppy adapter.

Also, I would remove both memory modules from the laptop and test just the memory on the motherboard by itself. When you are satisfied that there is not any problem with the built-in memory, then plug ONE module into the laptop and re-test. When done, remove that module and plug the other one in and test again. I know that this seems to be a lot of work, but I have seen problems pop up simply because of a combination of modules that do not play well together.

What if the on-board memory fails? Not much that you can do beside replacing the motherboard. Unless you have access to surface mount technology de-soldering equipment (and replacement memory chips), you would have very little chance in using a standard soldering iron. As noted above, if there is a way to disable the motherboard memory, then that could also work for you.