Support in other languages: 
Showing results for 
Search instead for 
Do you mean 
Reply
Ctrl-Alt-Del
umuteksi
Posts: 5
Registered: ‎01-04-2012
Location: Turkey
0
Accepted Solution

Memory Tests Fail When 2 DIMMs are inserted in my new IdeaPad Y470 LapTop!!!

Hi,

The second time I turned on my IdeaPad Y470 (i7-2630QM, 8GB RAM [2x4GB], Windows 7 Premium) and used it for resizing and uploading our trip photos to Google+, I encountered a BSOD in which I couldn't completely catch what the error message was. The part I caught was "MEMORY_*". So,as an experienced microelectronics engineer designing and testing chips, I decided to test the DIMMs (2x4GB) first. As a start, I used the Windows Memory Tester (press F5 during boot). And, voila!, I got memory errors but didn't note down the pass#. So, in order to isolate the problematic DIMM or potentially the faulty memory slot, I repeated the tests one DIMM at a time in each memory slot separately (so 4 trials total). Surprisingly, I got no failures although I waited ~4 hrs until pass# 50 in each trial. Then, I thought, maybe the windows tester is not sufficient so I tested the DIMMs again separately using Memtest86+ v4.20 by booting it from a USB stick to maximize the RAM that can be tested (minimum memory reservations). I pu each DIMM under test in both slots for 4+ hours (pass #4) each and still got no errors.

 

One thing I noticed was that the CAS timings would be set to 6-6-6-20 or 9-9-9-24 depending on which slot the DIMM is located. This is probably due to the Single-Channel or Dual-Channel modes. Anyway, so far the DIMMs seemed to be fine when used one at a time.

 

I repeated Memtest86+ tests after inserting both DIMMs. The CAS latencies were set to 9-9-9-24 automatically so no surprises there. During Pass#1 Test#6, i started to get memory failures being reported after ~ 1 hrs 13 mins. Then,  I turned off the machine, removed one of the DIMMs and restarted Memtest86 in less than 20 secs to keep the temperature at similar levels as when failure occurred. Surprisingly, Memtest86 didn't report any issues for while so I ended the test at pass #2 without any errors reported.

 

This again meant that the DIMMs are fine when used one at a time but not so when both were inserted. This is worrying as this may point to a chipset (memory controller) issue.

 

Ok, now again with 2 DIMMs in place, I got a failure in Memtest86 after ~ 1 hr 13 mins (same as before) and as soon as I got the error, I rebooted the machine and loaded Memtest86+ from my bootable USB stick as before and started the test right away in < 10 secs. This time, Memtest86 started reporting errors right away during pass #0 (as opposed to pass#1 before) in the first few seconds.

 

This was weird and probably points to a temperature/voltage/state issue however I would think any states would be cleared at boot time so it is probably a voltage/temperature build-up somewhere on the mainboard.

 

I did another trial: I waited for ~2 mins after I got errors in Memtest86 (with 2 DIMMs), rebooted to Memtest86 quickly again. This time I started to get errors after 1 hrs 16 mins during pass#1 same as before.

 

This means, that keeping the machine tuned off for a while after a failure helps but doesn't solve the problem completely. You get the errors in  1 hrs 10 something mins instead of the first few seconds.

 

I finally decided to boot Windows 7 with 2 DIMMs inserted and run prime95 and HCI Memtest. Using "Blend" test setting in prime95 64-bit v26.6, windows crashed with a BSOD after 34 minutes. Not good.

 

I started 4 instances of HCI Memtest to test the 8GB total RAM faster and got the first failure after ~10 minutes which crashed Windows. Not good either!

 

Based on these tedious trials which I should have to go through in the first place, I can safely conclude that I cannot use this laptop with 2 DIMMs inserted (i.e.. Dual-Channel Mode). This issue has nothing to do with Windows installation r drivers because I can repeat the failures using the stand-alone Memtest86 boot disk I which does not load any OS. The only thing ledt that I could check was the BIOS (which is independent of the OS). I tried to see if I can update the BIOS but I seem to have the latest version so it didn't let me update it.

 

Now, here i am, stuck with this laptop which I can only run reliably with only 1 DIMM (i.e.. 4 GB  at the moment). I bough it in the US but currently I am residing outside the US.

 

Dear Lenovo support team,

 

I am asking you to advice me on what to do under these circumstances. This is my first Lenovo laptop and I do not want this issue to spoil the image of Lenovo in my mind. Please consider that I am not a novice user but a user with a great deal of technical expertise in this field when replying my inquiry. I have already run the laptop through some extensive testing as you can see above. The memory issue is NOT RANDOM but is REPEATABLE. If you also agree that all these findings point to a HARDWARE problem (potentially the mainboard), I would like this laptop to be replaced with a new one which has to be put through a simple ~90 min testing using Memtest86+ with two DIMMs in place. I am really surprised and disappointed to see that Lenovo ships laptops to its customers without putting them through such simple reliability tests.

 

Best Regards,

 

Umut

Community Moderator
yigit
Posts: 13,391
Registered: ‎12-07-2009
Location: Antalya
0

Re: Memory Tests Fail When 2 DIMMs are inserted in my new IdeaPad Y470 LapTop!!!

hi umut,
to be honest, i don't think it's mainboard issue. it sounds like ram compatibility. as i experienced, it could happen when you use different brands/speed of rams.

to make sure, if you have minidump file, please, upload it so i can check it.

also, please, provide the bios version you have. ( or check download page for the bios update if there's any )


due to my absence, i may not reply your posts and/or personal messages

http://www.ki-themes.com
andyP
Posts: 9,295
Topics: 161
Kudos: 714
Solutions: 635
Registered: ‎11-27-2007
Location: Bonnie Scotland
0

Re: Memory Tests Fail When 2 DIMMs are inserted in my new IdeaPad Y470 LapTop!!!

umuteksi, welcome to the forum,

 

you certainly seem to have been very thorough in your testing and your patience whilst doing it is to be commended, not sure if I could stick out that amount of time playing with memtest86+ :smileywink:

 

I'm guessing you can only boot with a single RAM when it's in slot 0?  (Thanks Intel for that one), so testing a single RAM in the other slot was no goer?

 

I'm not familiar with the slot layout on the Y470, but something I experienced once with a ThinkPad was very similar.  IBM and Lenovo have always applied stickers to the holders on RAM slots. After a lot of testing I decided to clean the RAM slots and RAM contacts with contact spay and diluted isopropyl alchohol which actually solved the problem.  My conclusion was that at some point, maybe a failed attempt to attach one of the stickers, had left residue from the glue on the memory contacts.  This actually happened after I wrote this knowledgebase article. Check out the first picture, click on it to enlarge it.

 

I'm not saying this is the cause of your problem, just a possibilty that you may think worth looking at.

 

Regards

Andy  

______________________________________


Please remember to come back and mark the post that you feel solved your question as the solution, it earns the member + points

Did you find a post helpfull? You can thank the member by clicking on the star to the left awarding them Kudos

Please add your type, model number and OS to your signature, it helps to help you.

Forum Search Option

T430 2347-G7U W8 x64, Yoga 10 HD+, Tablet 1838-2BG, T61p 6460-67G W7 x64, T43p 2668-G2G XP, T23 2647-9LG XP, plus a few more.

FYI Unsolicited Personal Messages will be ignored.

de.gif  Deutsche Community   es.gif  Comunidad en Español  uk.gif  English Community ru.gif Русскоязычное Сообщество

PepperonI blog 

Ctrl-Alt-Del
umuteksi
Posts: 5
Registered: ‎01-04-2012
Location: Turkey
0

Re: Memory Tests Fail When 2 DIMMs are inserted in my new IdeaPad Y470 LapTop!!!

Hi yigit,

 

Thanks for the quick response.

 

I have not changed the original DIMMs that came with it (directly from Lenovo). It was the first thing i checked however they are exactly the same memory modules with Samsung branded chips. Even their serial numbers differ by one (one ends with letter C the other with D). Memtest86+ also reports exactly the same model number for both DIMMs. Screen shot:

 

https://rapidshare.com/files/427526710/Memtest86_screenshot.jpg

 

But, since you asked for it, here is the latest Minidump:

 

https://rapidshare.com/files/2102616814/010512-23368-01.dmp

 

The BIOS version:

 

47CN30WW

 

Let me know if I can provide any other data to help you debug.

 

Cheers,

 

Umut

Ctrl-Alt-Del
umuteksi
Posts: 5
Registered: ‎01-04-2012
Location: Turkey
0

Re: Memory Tests Fail When 2 DIMMs are inserted in my new IdeaPad Y470 LapTop!!!

Hi Andy,

 

Actually, I can boot just fine with one of any of the two DIMMs regardless of which of the two slots it is in as long as I have only one DIMM in the laptop. Actually, in order to eliminate the "bad slot" factor, I also ran tests for both DIMMs placing them seperately one at a time in each slot (mentioned in my original post) and both DIMMs came out just fine. So, the slots and the connectors/ports seem to be in good shape. Actually, the DIMMs themselves are also in good shape when tested one at a time. The problems pop up whenever I have two DIMMs in place. I am afraid it resembles a typical signal integrity issue either on themainboard (excessive resistive voltage drop on motherboard power traces supplying the DIMM slots when two DIMM's are drawing current at the same time)  or a defective/marginal memory controller logic which starts malfunctioning at certain temperatures/voltage levels. The fact that keeping the laptop powered off for a while delays the occurance of these errors also suports that this issue is most likely voltage or temperature related.

 

Cheers,

 

Umut

andyP
Posts: 9,295
Topics: 161
Kudos: 714
Solutions: 635
Registered: ‎11-27-2007
Location: Bonnie Scotland
0

Re: Memory Tests Fail When 2 DIMMs are inserted in my new IdeaPad Y470 LapTop!!!

[ Edited ]

Hi Umut,

 

I guess you've covered all the bases and need to get in touch with support to find out the quickest way of solving the situation.  It's certainly a rare one and I am certain that explaining your diagnosis efforts, methods and conclusions as clearly as you have here will lead to a speedy conclusion.

 

It's probable that they wont be able to fulfill your wish to receive a replacement system that has been tested for 90 minutes, but kindly requesting can't hurt. Maybe you could give them a call to discuss the possibilities?

 

As you purchased the system in the US and are currently in Turkey a replacement system may be out of the question, (the addage take it back to the shop where you bought it), but please do give them a call and explore the possibilities and please do let us know how you get on.

 

edit; typo

Andy  

______________________________________


Please remember to come back and mark the post that you feel solved your question as the solution, it earns the member + points

Did you find a post helpfull? You can thank the member by clicking on the star to the left awarding them Kudos

Please add your type, model number and OS to your signature, it helps to help you.

Forum Search Option

T430 2347-G7U W8 x64, Yoga 10 HD+, Tablet 1838-2BG, T61p 6460-67G W7 x64, T43p 2668-G2G XP, T23 2647-9LG XP, plus a few more.

FYI Unsolicited Personal Messages will be ignored.

de.gif  Deutsche Community   es.gif  Comunidad en Español  uk.gif  English Community ru.gif Русскоязычное Сообщество

PepperonI blog 

Community Moderator
yigit
Posts: 13,391
Registered: ‎12-07-2009
Location: Antalya
0

Re: Memory Tests Fail When 2 DIMMs are inserted in my new IdeaPad Y470 LapTop!!!

it just points that your issue is memory management.
please, check if you have international warranty ( iws ).

by the way, is it possible you to use different memory sticks to make sure it's memory issue?

http://consumersupport.lenovo.com/uk/en/warranty/Warranty.html


due to my absence, i may not reply your posts and/or personal messages

http://www.ki-themes.com
Ctrl-Alt-Del
umuteksi
Posts: 5
Registered: ‎01-04-2012
Location: Turkey
0

Re: Memory Tests Fail When 2 DIMMs are inserted in my new IdeaPad Y470 LapTop!!!

hi yigit,

 

unfortunately, it is not possible for me to test it with different memories at the moment. that would be a great experiment though.

 

however, another option I can think of, in fact, a question for you:

 

is there a custom (not necessarily official) BIOS available that I can use temporarily to  modify the memory timing parameters and /or voltages to test them with some additional room to compensate for any potential degradation that could be present due to voltage/temperature?

 

I couldn't spot any such options in the current BIOS I have.

 

Umut

Community Moderator
yigit
Posts: 13,391
Registered: ‎12-07-2009
Location: Antalya
0

Re: Memory Tests Fail When 2 DIMMs are inserted in my new IdeaPad Y470 LapTop!!!

i'm not sure the site below has a modified bios for you but i do nt suggest you to use it. still, if you want, use it on your own risk.
http://www.bios-mods.com/forum/index.php

also, it'd be safer to check the ram sticks. if you order it online, you'll be able to return it in 7-14 days.


due to my absence, i may not reply your posts and/or personal messages

http://www.ki-themes.com
Ctrl-Alt-Del
umuteksi
Posts: 5
Registered: ‎01-04-2012
Location: Turkey
0

Re: Memory Tests Fail When 2 DIMMs are inserted in my new IdeaPad Y470 LapTop!!!

Thanks for all the suggestions folks.  I was fortunately able to isolate the problem through more tedious testing using prime95: one of the Samsung DIMMs is marginally operational. prime95 now can now run for a minimum of 14hrs (even more but I terminated it manually) so the machine is rock solid without that DIMM. I even added a 2GB Kingston DIMM to get 6GB in total and it also passes my prime95 criteria with this config.