[memtest86+] Bad memory or bad controller?

Hello, I need some advice from somebody who understands RAM and Memtest86+ better than I do.

System memory: 2x 2048MB DDR1333 9-9-9-24
fails on memtest test #7 (random number sequence)
both BIOS and memtest detect/report 3838MB RAM instead of 4096 so it seems the bad memory is already being discarded(?) do I understand this correctly?

Curiously,
– other memtest tests pass without error;
– the situation is perfectly symmetrical over the two memory banks*;
– can move the memory banks between (4) slots, makes no difference.

  • in particular, I can run memtest with one at a time, and I get the same identical errors, and detection of 1919MB instead of 2048MB.

I find it strange that two memory banks became damaged in exactly the same way, to exactly the same extent, at exactly the same time.

Can someone confirm to me:
– is this a case of bad memory, i.e., will I resolve by replacing the RAM, or could there be a motherboard/cpu (memory controller) issue?
– in the short run, is it “safe” to use this memory (because BIOS seems to detect & exclude the bad blocks), or should I avoid using until replaced?

Thanks for any advice.

I would guess that some memory is being reserved, or assigned to the video card or to some other purpose, and so is not seen in your testing.

On 03/06/2013 04:36 PM, Kalenz wrote:
> I find it strange that two memory banks became damaged in exactly the
> same way, to exactly the same extent, at exactly the same time.

that is some GOOD mojo you have there!!

you didn’t say which openSUSE you have there (and should always) but
i am gonna mojo out on a limb and predict you have an openSUSE 12.2
install disk, from which you are running memtest…right??

if so, go to the release notes here:
https://www.suse.com/releasenotes/x86_64/openSUSE/12.2/

and scroll down to “3.2. Pre-installation Memory Test Incorrectly
Identifies Good Memory as Bad” where it says:

The pre-installation memory test (memtest) on the openSUSE 12.2 media
got miscompiled. It reports errors in test 7 on good RAM modules. Use
the openSUSE 12.1 media if you need to run memtest.

or could download a 12.3 RCx Live CD from

and thereby have (maybe, i have not checked!) a newer version of
memtest86


dd
http://tinyurl.com/DD-Caveat

That’s some pretty good guesswork you’ve got going there. I just ran memtest from 12.3RC2, and it completed without error.

Note to self: read the release notes. :wink:

Thanks for the help!

> Note to self: read the release notes.:wink:
>
> Thanks for the help!

welcome…and, it was 12.2 that taught me to read the release notes, too!


dd