14 Replies Latest reply: Nov 11, 2013 9:45 AM by E.Halderman
mynameismyname Level 1 Level 1 (5 points)

Due to frequent shutdowns that have been associated with hardware issues (covered under a separate thread), I decided to run Memtest to check my RAM.

 

I have a total of 5 GB RAM (2 x 512MB + 2 x 2GB).  The suspicion I have is that the original, 512 is at a 4200 speed, while the added, 2 GB are rated by my Mac's System Profiler as 3200 (Crucial claimed there's no 4200 available anymore).

 

Also, I did a regular restart before running Memtest (via the Terminal), because when trying to start up as single-user (Command-S) I got a DOS-like screen that was not at all clear to me....  IS THAT CONNECTED WITH THE FOLLOWING MESSAGE (see below, copied from the report)? And if so, how significant is this "error" of testing with unlocked memory?

 

Attempting memory lock... ERROR: Memory lock failed - reason unknown.

WARNING: Testing with unlocked memory may be slower and less reliable

 

Here is the report, and I would greatly appreciate getting a feedback, telling me if all OK, or are there any issues with my RAM:

 

---------------------------------------------

 

Last login: Fri Oct 19 17:33:46 on console

(my name)s-power-mac-g5:~ Ami$ memtest all 2

 

Memtest version 4.22 (64-bit)

Copyright (C) 2004 Charles Cazabon

Copyright (C) 2004-2008 Tony Scaminaci (Macintosh port)

Licensed under the GNU General Public License version 2 only

 

Mac OS X 10.5.8 (9L31a) running in multiuser mode

Memory Page Size: 4096

System has 2 PPC processors(s) with Altivec

Requested memory: 4531MB (4752113664 bytes)

Available memory: 4531MB (4752113664 bytes)

Allocated memory: 4531MB (4752113664 bytes) at local address 0x0000000001000000

Attempting memory lock... ERROR: Memory lock failed - reason unknown.

 

WARNING: Testing with unlocked memory may be slower and less reliable

 

Partitioning memory into 2 comparison buffers...

Buffer A: 2265MB (2376056832 bytes) starts at local address 0x0000000001000000

Buffer B: 2265MB (2376056832 bytes) starts at local address 0x000000008e9fc000

 

Running 2 test sequences... (CTRL-C to quit)

 

Test sequence 1 of 2:

 

Running tests on full 4531MB region...

  Stuck Address       : ok             

  Linear PRN          : ok             

Running comparison tests using 2265MB buffers...

  Random Value        : ok

  Compare XOR         : ok

  Compare SUB         : ok

  Compare MUL         : ok

  Compare DIV         : ok

  Compare OR          : ok

  Compare AND         : ok

  Sequential Increment: ok

  Solid Bits          : ok             

  Block Sequential    : ok                

  Checkerboard        : ok             

  Bit Spread          : ok               

  Bit Flip            : ok               

  Walking Ones        : ok               

  Walking Zeroes      : ok               

 

Test sequence 2 of 2:

 

Running tests on full 4531MB region...

  Stuck Address       : ok             

  Linear PRN          : ok             

Running comparison tests using 2265MB buffers...

  Random Value        : ok

  Compare XOR         : ok

  Compare SUB         : ok

  Compare MUL         : ok

  Compare DIV         : ok

  Compare OR          : ok

  Compare AND         : ok

  Sequential Increment: ok

  Solid Bits          : ok             

  Block Sequential    : ok                

  Checkerboard        : ok             

  Bit Spread          : ok               

  Bit Flip            : ok               

  Walking Ones        : ok               

  Walking Zeroes      : ok               

 

All tests passed!  Execution time: 15404 seconds.


Mac OS X (10.5.8), 5 GB Ram
  • 1. Re: Memtest report, can you help reading it?
    BDAqua Level 10 Level 10 (116,480 points)

    Question: When I run "Rember", It gives me an error message:

    "Attempting memory lock... WARNING: Testing with unlocked memory may be slower and less reliable

    ERROR: Memory lock failed - reason unknown."

    What does this mean, and what should I do?

    Answer: The error message is stating that the machine cannot "lock" the memory (which allows for faster and more precise testing).

    http://kelleycomputing.net/support/rember/

  • 2. Re: Memtest report, can you help reading it?
    japamac Level 7 Level 7 (24,390 points)

    Requested memory: 4531MB (4752113664 bytes)

    Available memory: 4531MB (4752113664 bytes)

    Allocated memory: 4531MB (4752113664 bytes) at local address 0x0000000001000000

    Attempting memory lock... ERROR: Memory lock failed - reason unknown.

    That's the in excess of 4 GB lid for 32 bit systems.

    A benign error.

     

    If you like, pull a pair of DIMMs and run again.

    The error should not occur with less memory.

     

    (Crucial claimed there's no 4200 available anymore)

    If Crucial sold you memory slower than what you need (the report is actually true) then you have a problem.

    ASD (Apple Service Disc) notes refer to issues in systems with memory that is slower than the system is rated for.

     

    Slower than spec RAM could be the reason for the system/CPU hangs that you experience.

     

    Crucial may not have the proper RAM, but OWC does:

    http://eshop.macsales.com/item/Other%20World%20Computing/4200DDR2M4GP/

  • 3. Re: Memtest report, can you help reading it?
    japamac Level 7 Level 7 (24,390 points)

    Also, I did a regular restart before running Memtest (via the Terminal), because when trying to start up as single-user (Command-S) I got a DOS-like screen that was not at all clear to me....

     

    In Single User mode, all that you have to do is type a command and press Enter.

    Type

    /Applications/memtest/memtest all 3 -L

    and press Return.

     

    To boot into single-user mode, hold down the "Command" and "S" keys during startup. You will be automatically logged in as the user root with a minimal command line environment. The login directory for the root account is "/" which is the top-level directory of the boot volume. Assuming that the memtest folder resides in your Applications folder, a typical invocation of memtest would be the following:

     

    >  /Applications/memtest/memtest all 3 -L <RETURN>          ( <RETURN> means press the Return key)

     

    This would run three passes of the test suite, testing all available free memory. The "-L" switch instructs memtest to save the transcript of the run to a file named "memtest.log" within the working directory from which you invoked memtest

     

    Read the instructions. It's all in there......

    User Guide - Memtest OS X

  • 4. Re: Memtest report, can you help reading it?
    mynameismyname Level 1 Level 1 (5 points)

    Slower than spec RAM could be the reason for the system/CPU hangs that you experience.

    So the fact Memtest did not come up with errors means the DIMMS are ok, but that doesn't mean my Mac is happy with the slower speed, right?

     

    The truth is I've had those DIMMS for 3 years now w/o problems till lately... I SUSPECT that upgrading from Tiger to Leopard made my Mac more sensitive and less stable because of it.... Crucial claims they've sold many of thise w/o any issues. They're actually shipping me replacement RAM for free, same 3200... This was before I ran memtest... I know that OWC has 4200 at about $70 for the 2 x 2BG.  I may chose to get theirs.

     

    Type

    /Applications/memtest/memtest all 3 -L

    and press Return.

    Memtest is not an application, and it doesn't reside in the Application folder.

  • 5. Re: Memtest report, can you help reading it?
    japamac Level 7 Level 7 (24,390 points)

    Memtest is not an application, and it doesn't reside in the Application folder.

    If it isn't an application, then what is it???

     

    Where ever you put the Memtest Application. If it's on the Desktop, Type Desktop. If its in Downloads, Type Downloads.

     

    but that doesn't mean my Mac is happy with the slower speed, right?

    IF the RAM is, IN FACT, not PC4200 and is a slower, PC3200 DIMM, it isn't the right RAM and will cause issues, sometime, somewhere. I have a hard time believing that the machine actually runs.

     

    hat upgrading from Tiger to Leopard made my Mac more sensitive and less stable because of it

     

    Leopard is far more discerning regarding RAM.

     

    Crucial claims they've sold many of thise w/o any issues. They're actually shipping me replacement RAM for free, same 3200

     

    I don't buy it. PC5300, OK, but not slower. Many people got Crucial PC5300 and it works, but always misreports as PC3200.

    What does the sticker on the side of the DIMM say?

     

    For anyone reading (because RAM is important and misinformation and confusion is bad):

     

    • NEVER install RAM that is slower than spec'd RAM.

     

    • In the Dual Core G5, since DDR2 PC4200 DIMMs are harder to find, many people opt for DDR2 PC5300 DIMMs. That is likely fine, as the RAM will be backwards compatible to the slower 533 MHz controller of the G5.

     

    • Misreports ARE common with the faster RAM, however.

     

    • Do NOT install DDR2 PC3200 DIMMs as they are not rated beyond 400 MHz.

     

  • 6. Re: Memtest report, can you help reading it?
    mynameismyname Level 1 Level 1 (5 points)

    Japamac,

     

    Rember is an application, but Memtest is not. Check about it, I also read it somewhere...

     

    As to my Crucial DIMMS, they're inside the Mac, so I'm not sure what's printed on their label, BUT I talked to Crucial 2 days ago, before running the Memtest, when I was still suspicious that my crashes were due to their RAM, and even though they were claiming that 3200 should be working, they were willing to ship me new RAM to replace my existing ones (a free swap). The online invoice does mention 5300.  Now, once I install the new DIMMS, you say they would still regsiter as 3200 in my System Profiler?  But it should still be OK?

  • 7. Re: Memtest report, can you help reading it?
    japamac Level 7 Level 7 (24,390 points)

    Jeez, now you will argue that a command line utility is not an application???!!!!

     

    If you know everything, why do you ask?

     

    You don't seem to believe anything that I tell you.

     

    I'm tired......

  • 8. Re: Memtest report, can you help reading it?
    Allan Eckert Level 8 Level 8 (41,525 points)

    Remember everyone here is a volunteer and NOT an Apple employee. They are only responding to you out of the kindness of their hearts. They don't have to do that.

     

    In all of the postings I seen from Japamac so far I have never seen one of his with the wrong information. He is one of the best users I have seen on this forum.

     

    Allan

  • 9. Re: Memtest report, can you help reading it?
    mynameismyname Level 1 Level 1 (5 points)

    Japamac, no need to be tired so quickly (I don't seem to believe anything that you tell me? Really, Japamac, you start reminding me of my previous wife :-) :-) :-) ) the issue here is not whether Memtest is an application or not, I mentioned it 'cause if I'm suppose to start up as Single-User and type in the command you suggested, namely  /Applications/memtest/memtest all 3 -L to MY understanding it won't find Memtest there, since there's no such an application there (I searched for it)....

     

    BTW, you can check more about it here, others were wondering about it also:   http://macmost.com/forum-an-app-to-test-ram.html   and I quote:  "This is a command-line tool, which means you run it in the Terminal"  or  "it is not an application that can be run from the Finder. It is a command line tool."

     

    Either way, I think I've learned a few things about my RAM, and I thank you for your helpul suggestions.

  • 10. Re: Memtest report, can you help reading it?
    japamac Level 7 Level 7 (24,390 points)

    to MY understanding it won't find Memtest there, since there's no such an application there (I searched for it)....

     

    The application Memtest is where ever you put it AFTER you downloaded it.

    Of course it's not in Applications UNLESS you put it there OR downloaded it TO Applications.

    It's not part of the OS X install, is it?

    , I think I've learned a few things about my RAM,

    But you don't wish to learn, PROPERLY, how to BEST utilize the APPLICATION (YES, a command line tool IS an application).

     

    Whatever.

     

    You know better. Good luck with the CPU hangs.

  • 11. Re: Memtest report, can you help reading it?
    BDAqua Level 10 Level 10 (116,480 points)

    Indeed!

  • 12. Re: Memtest report, can you help reading it?
    mynameismyname Level 1 Level 1 (5 points)

    ...When I launched the Memtest installer, all it was asking is to select which HARD DRIVE to install into, nothing beyond that, so naturally I couldn't know or control into which FOLDER it would go into, AND I STILL DON'T KNOW WHERE IT RESIDES, since spotlighting "Memtest" shows NO RESULTS, beyond the installer pkg.

     

    Not sure why you refuse to believe me, I'm not expressing an opinion here, I'm telling facts..... But let's leave it aside.

     

    The good news is, SO FAR, this is the 3rd day, seems like my Mac is behaving well.  In a couple days, when I get the new RAM I will install it, and run Memtest again (this time trying restarting in Single-Mode), just to be on the safe side, before shipping back my old DIMMS, even though I'm not at all sure there IS/WAS a problem with my current DIMMS (especially if they have 5300 printed on their lanels, which I will check once I do the swap).......

     

    Thanks for all your help, Japamac.

  • 13. Re: Memtest report, can you help reading it?
    r0k-dot-org Level 1 Level 1 (0 points)

    in terminal, type

    which memtest

     

    On my Mac, the system replies with...

    /usr/bin/memtest

     

     

    This means that on my Mac it says memtest is in /usr/bin/memtest

     

    if I were to boot in single user mode and run memtest, I would run it with the following command:

     

    /usr/bin/memtest all 2

     

    I have 16 GB of Centon RAM in a late 2011 MBP.  I've had a few crashes and kernel panics so I reluctantly ran memtest.  So far there are two errors so I guess I'll find the time to boot in single user mode and run it on all of my RAM.  I know I'll have to swap back my factory 4 GB if I keep finding errors with memtest or getting the occasional kernel panic.  BTW, behaving well for a period of time is not as important as loading up memory and behaving well.  For me, iPhoto is the culprit that causes the panic.  Perhaps it's because I have about 10,000 faces but iPhoto crashes pretty reliably if I bring up my daughter's face (she has about 2000 of those 10,000 pictures).

     

    The next time I install RAM, I'll run memtest the same day. Darn. Looks like the data mismatch occurred in the same spot on the second pass as well.  I pretty much have to dig into this further. 

  • 14. Re: Memtest report, can you help reading it?
    E.Halderman Level 1 Level 1 (0 points)

    .