memtest v6.1.0 puzzle

[seekingbuddha]

I have searched around the net for long time, and could not find an answer to my puzzle. So, i have enrolled into this forum to get the right answer from the Oracle itself. I have a mid-2009 Macbook pro running Intel Core2 Duo. I have found the right version of memtest because this firmware needed a modified version of memtest86, and installed it to a USB. Upon running this test, with the original Apple RAM memory of 2GB, the test completed 4 passes in about 3.5 hours. I ran it one more time, to be sure and you can see that it is nearly done in the following image.

I will continue the post in next message, because I want to present the first screenshot here. Please read all 3 messages, to get the full picture.

[seekingbuddha]

I upgraded to 8GB, using Crucial (Micron) memory from amazon.com sold by Crucial. You can see the memory specs on the screenshots below - i confirmed that they were compatible, using crucial.com site info. What is puzzling to me is the fact that memtest86 took a long time (as seen in screenshots below) to complete, when compared to the 2 tests (4 pass each) i did with the original apple RAM of 2GB. I am here in this forum to confirm that it is normal to see this (more than 2 fold) increase in time taken by memtest86. I am thinking that this increase in time is due to the fact that memory jumped from 2GB to 8GB on upgrade. Is this correct ? Or, am i looking at potential trouble with this new RAM sticks down the line ?

There were no errors produced even after 15 hours, which gives some degree of quality assurance on the new RAM. But, when I timed (using a stop watch) the time it took to boot, I did not see significant change. Both 2GB as well as 8GB took 1.5 minutes to boot this Macbook (loading Firefox, Safari and Activity Monitor). If i do not have any applications running, it took about 1 minute to boot (both 2GB as well as 8GB). Perhaps the 8GB gave about 2 seconds faster boot. I also tested the time it took to load about 10 tabs in Firefox browser, using both RAM configurations. Again, the time difference between 2GB and 8GB was only couple of seconds. I ran these boot tests multiple times, to arrive to confirm the durations.

I must acknowledge that I am an experienced computer geek, and not a newbie to things. So, i do understand that RAM increase is mainly meant for running multiple applications in parallel and boot time increases are mainly seen by other hardware upgrades (like SSD in place of HDD). But, i am a bit puzzled at the fact that there is absolutely no change in boot time or Firefox 10 tab test. I did reset the NVRAM and SMC whenever i changed RAM for these tests, just to be sure. This would be insignificant factor, because mostly I put the macbook to sleep, rather than shutting down and rebooting every time. It only gets a reboot about once a month (if I notice any system slowdown).

Thanks for all the replies. I have taken 3 screen shots during different runs of memtest86. Hence the screenshots show different durations at which the test was terminated.

[seekingbuddha]

In addition, I should mention that this Macbook pro is running brand new installation of OS X Mavericks that got loaded recently by the Apple store and there is nothing else on this machine. I ran the firefox test by clicking on all 10 tabs, one after another because firefox does not load all 10 tabs upon startup automatically (like Safari does). Firefox took about 25 seconds to load these websites consistently with variation of only few seconds - it did not matter if it was 2GB or 8GB memory. Activity monitor showed that there was no swap file usage in both cases. My main concern is to make sure that the new memory sticks are good and will not fail after few months because I have read amazon reviews on this Crucial RAM and some have reported RAM failure after few months of usage. Of course, there is lifetime warranty on these, so I only am concerned about the long durations for performing memtest on 8GB.

[seekingbuddha]

Does anyone from Passmark support monitor these forums ? There are 57 views of this thread so far. I am surprised there is no answers yet. Would it help if i call the company for some clarifications ? I was hoping for a tech support answer here.

[keith]

I only am concerned about the long durations for performing memtest on 8GB.

Yes, the more RAM you have, the longer the memory tests will take to complete in MemTest86. This is especially true for the longer tests (from Test 7 onwards). Going from 2GB -> 8GB means that MemTest86 will have to go through 4x as much memory during the tests.