understanding test results- please clarify.

[mem-noob]

Hi

Not sure with the results below whether I need to replace any of the 8GB memory or not in my Thinkpad. Would be grateful for clarification:

3 hrs, 15 mins
Iterations: 81
Pass: 4
Errors: 0
Error confidence value: 213


Lowest error Address: 126.5mb
Highest error Address: 2410.4mb
bits in error: total 8 min: 3 max: 7 Avg: 4
max contiguous errors: 2

Thanks!

[David (PassMark)]

Would be good to see a photo of the screen, as some of the numbers you transcribed look a bit strange.

But it is reasonably likely that the RAM is (slightly) bad. But even being just a bit bad is enough to cause occasional crashes and data corruption. There is also a smaller chance that it is your CPU or motherboard or some external factor (over heating, radiation, power spike, etc..).

Would be worth running it again to make sure it isn't a one off problem.

Were you getting some other bad behavior from the machine that lead you to suspect bad ram?

[mem-noob]

Hi and thanks

I've been using this Kingston memory (2 x 4GB) for a year and a half and the only (possible) issue has been that the software music player I use (that pre-loads ones chosen music playlist into RAM) isn't functioning to it's fullest potential.

I do currently have a serious problem with high latency (drop outs) with any audio played on the laptop. However, this has only started since the system board was changed a few weeks ago (due to a faulty video connector). I guess its something to do with the LAN adapter, rather than ram-related, because the drop outs stop when there is no internet connection. The problem still persists after three new boards!

I will do the test again and take a picture, but how long should I let it run for? BTW, pressing ESC didn't end the test- I had to press the power button in the end.

[David (PassMark)]

The ESC key doesn't immediately terminate the test. It requests the tests to finish after the current test, which depending on the current test can take a few seconds or a minute to finish up.

Sounds like you have a collection of problems. Drop outs in audio playback only when you have an active network connection won't be RAM related. I also think this this is unlikely to be the motherboard (especially if you have changed the mother board 3 times and seen no change in the audio playback). More likely to be the network card device driver, or some system task making requests to the internet and blocking other activity while this is taking place. i.e. maybe a software issue and not a hardware issue.

If it took 3 hours to get the RAM error, then I would try it again for a similar period. Normally 1 pass should detect most errors.

[mem-noob]

thanks, David. Will redo test later.

[mem-noob]

Hi again

I still had to press restart on my pc, five to ten minutes after pressing ESC.
This time it said: Time 4 hrs, 4 mins, Iterations 240, Pass 4, Error 0.

http://i204.photobucket.com/albums/b...5/DSCF2720.jpg

[Michael (Passmark)]

We believe we've replicated this issue locally. It seems to be an issue with keyboards connected via USB. We have a fix for this internally now, however in the meantime you can get around this by using a PS2 keyboard, or simply waiting for the program to move onto the next test, at which point the keyboard should start accepting inputs again.

[mem-noob]

it's no problem anyway- just thought I'd mention it.

So, the second test above is a complete pass, and I should ignore the first?

[David (PassMark)]

There probably is or was some real error with the RAM. But if it takes 7 hours of testing to get 1 error, then you can't blame the RAM error for getting consistent audio playback problems.

It is possible to have one off errors 'soft' errors with RAM, which disappear with subsequent testing. There are often caused external radiation or EMI.

From Wikipedia,
"Electrical or magnetic interference inside a computer system can cause a single bit of DRAM to spontaneously flip to the opposite state. The majority of one-off ("soft") errors in DRAM chips occur as a result of background radiation, chiefly neutrons from cosmic ray secondaries, which may change the contents of one or more memory cells or interfere with the circuitry used to read/write them."
But the studies also say that there is "evidence that most such errors are intermittent hard rather than soft errors".

I would be tempted to ignore the potential RAM errors for the moment and look at the audio / network issue instead, as this is surely causing you more problems than the RAM.

[mem-noob]

There probably is or was some real error with the RAM. But if it takes 7 hours of testing to get 1 error, then you can't blame the RAM error for getting consistent audio playback problems.

It is possible to have one off errors 'soft' errors with RAM, which disappear with subsequent testing. There are often caused external radiation or EMI.

From Wikipedia,
"Electrical or magnetic interference inside a computer system can cause a single bit of DRAM to spontaneously flip to the opposite state. The majority of one-off ("soft") errors in DRAM chips occur as a result of background radiation, chiefly neutrons from cosmic ray secondaries, which may change the contents of one or more memory cells or interfere with the circuitry used to read/write them."
But the studies also say that there is "evidence that most such errors are intermittent hard rather than soft errors".

I would be tempted to ignore the potential RAM errors for the moment and look at the audio / network issue instead, as this is surely causing you more problems than the RAM.

Actually, my laptop is far too close to a loudspeaker (10" vintage JBL driver with very large magnet), so thanks for making me realise that.

As regards the system board issue, it appears that others have reported the same, so it may be the boards after all. I'm currently negotiating a resolution with IBM.

Thanks for your help.

[mem-noob]

FWIW, an update: IBM are replacing my notebook with a new IB one. Seems somewhat drastic considering it's a network driver-related issue but the rep thinks there might be an error on the replacement boards supplying too much voltage, somehow. I'm not complaining anyway.

This time around when I upgrade the memory to 8GB, I will be doing memory tests immediately rather than waiting over a year to do it- and returning it, if need be.

Any recommendations for brand of memory for 2 x 4GB (PC-3 12800 1600 Mhz) appreciated. TIA..

[David (PassMark)]

Most motherboard manufacturers have a list of RAM that they have tested with. So it makes sense to have a look for this list first.

[mem-noob]

got ya, thanks a lot..