04-23-2012 06:49 PM - edited 04-23-2012 08:53 PM
I bent the metal fingers on my memory hatch door to a degree where I was certain they were contacting the grounding strips. I then proceeded to rub my laptop vigorously across a fleece blanket. No shutdown occured, so I am inclined to believe one of the problems I was experiencing was static discharge from improper contact to ground on that hatch door. Bending the metal fingers down solved the static discharge problem for me.
I then tested the second type of shutdown I have been experiencing. I enabled CPU power management and ran a workload that had caused sudden shutdowns before. This workload is still a problem. I created a screen capture showing a reliable way to reproduce a sudden shutdown with CPU power management enabled. On my laptop, this triggers the sudden shutdown on both Linux and Windows. The screencast is available here: http://youtu.be/ROugtB5vWxw
Brief Overview of steps shown in the screencast:
-server -Xmx1024m -XX:MaxPermSize=512m
4. Login to http://localhost:8080/magnoliaAuthor/ (default credentials are superuser/superuser)
5. From the left sidebar select Tools -> Export
6. Choose the website repository and Zip compression
7. Click Export
8. Wait several minutes for the export. Before it completes, the laptop will shutdown and restart, no BSOD, no diagnostics.
Update: Before I turn in for the night, here's a video I captured from my phone showing the shutdown in progress. You can see it happen towards the end of the vid: http://youtu.be/tFop1UAK8fo
When I disable CPU power management and follow the same series of steps, no shutdown occurs.
I invite anyone else who has experienced sudden shutdowns with CPU power management enabled to test the above workload (with the setting enabled). I have a feeling it will trigger the shutdown for other people as well. For me it is 100% reproducible with these steps. Disable CPU power management, and no shutdown will occur.
04-23-2012 07:20 PM
Thanks for sharing this information.
I have no idea what the CPU power management BIOS setting has to do with this problem.
In your previous post, you mentioned finding a bad DIMM. Is your failing workload with or without this bad DIMM installed? Have you tried removing/swapping the other DIMMs, one at a time, to see if your workload can run successfully? Even if a DIMM passes memtest, please try this experiment.
Also - this is a real shot in the dark - does your system have a WWAN device?
04-23-2012 07:28 PM
This failing workload is with the bad dimm removed, and I do not have a WWAN device installed.
I will test removing 1 of the remaining dimms at a time and repeating this workload, but I will have to do that tomorrow -- between losing a dimm to static discharge, restoring corrupted files from backup, and running this workload test, I am now very much behind on real work. Hopefully in the meantime someone else who has seen sudden shutdowns with CPU power management enabled will be able to replicate these results.
04-24-2012 08:03 AM
I have been a Lenovo W520 buyer/user for close to a year now and I have been experiencing these sudden shutdowns
- like the battery is pulled screen turns black
- occurring once every 3 days or so (but more frequently recently)
- usually during low load or in idle
I have a W520 - intel core i7-2720QM CPU 2.2GHZ - 8GB RAM and basically shut-downs started from the day I bought it
I had all diagnostics and antivirus run many times before, recently got tech support involved who said it was probably a software-hardware conflict - and I should reinstall windows/reimage. Then I was even stupid enough to buy Lenovo Premium Support who did again all diagnostics etc. and ended up with nothing.
Only then I found this forum... which clearly points to hardware issues. I want to make sure I am getting more current feedback on this issue (so far lenovo support did not make me aware these are more structural W520 issues) and get this fixed (whenever a permanent fix becomes available) within my warrantee as I have reported it well within warantee time, but it won't last all that much longer.
so far I have seen the following help
- disabling CPU Power management in BIOS
- replacing DIMM (or bending some metal around it to get rid of static interactions?)
- replacing motherboard
- disabling graphics card settings/usage (potentially related to CPU power management in BIOS)
- getting a new machine
if I am missing anything else here, please let me know..
I am no lenovo/laptop expert, but did find it remarkable that when I just bought it my windows experience index was limited by the hard-disk transfer rate (got a 5.9) but when I checked last time that changed to Desktop performance for Windows Aero listed as the lowest (getting a 5.5). might this point to graphics card/power management issues?
feedback very welcome - I really want to get this issue solved - and within (my still valid) warrantee -
contact customer support again?
04-24-2012 08:07 AM
just to clarify my previous post -
my list of seeing things that help is my summary of all things posted as help (getting rid of shutdowns) in this (long) thread so far..
04-28-2012 02:31 PM
I purchased W520 (427637U) 7/30/2011.
Experienced spontaneous shut down on average every few days.
3/2/2012 replace motherboard. No effect, still spontaneous shutdown.
3/19/2012 replace motherboard, fan and CPU. It has been without spontaneous shutdown as of today, 4/28/2012.
I think it is safe to say my W520 is fixed.
I do have onsite service which made things happening much faster.
(I am NOT advertising for them, but to remind one can check lenovo web site to see if onsite still available for one's machine.)
04-29-2012 12:59 AM - edited 04-29-2012 01:01 AM
After this, I started to look at the ram bay itself. The bay cover has a metal shield which connects to the laptop frame for grounding via 4 metal fingers (two on each side) and conductive foam on the laptop frame. This metal shielding should stop any static charge from interfering with the ram. However, the metal fingers on the bay door do not stick out very much. It seems that they could not be not connecting with the metal foam on the laptop frame, leaving the ram bay door electrically floating and the ram prone to interference.
@Weston - I have attached the photo of my RAM bay cover inside site, I am not sure what are the 4 metal fingers (two on each side) you are referring to?
On April 10th I have bent the 8 metal fingers (4 on the left and 4 on the right side) and was running without SSS and with enabled CPU power management. But tonight I have had another SSS. Therefore I am curios how yours RAM bay cover inside looks like.
04-29-2012 01:49 AM - edited 04-29-2012 01:50 AM
My RAM bay cover is exactly the same as yours.
2 days ago I also had a SSS. I do believe however that while moving my laptop I touched the VGA connector, which may had caused electric discharge and brought my W520 to shut-off immediately.
Maybe the same happened to you. Please try to recall how exactly you were holding your PC.
Apart of that one incident, my W520 has been rock-stable.
04-29-2012 07:48 AM
On April 10th I have bent the 8 metal fingers (4 on the left and 4 on the right side) and was running without SSS and with enabled CPU power management. But tonight I have had another SSS.
Maybe the metal parts returned to their original shape?
04-29-2012 08:05 AM
The SSS happened in the night, no movement, no cats around . So I am pretty sure no movement had happened and VGA port was not touched either.
I always leave W520 powered on during the night in order to test the SSS behavior. In my case the SSS always happens in the time W520 being in idle and mostly in the night while heavily used during the day.
Following the ColonelONeill remark, I have re-bent the metal fingers but if that is the case than it would be only the temporarily solution, because soon or later the metal fingers will move back to original position.
I will test now if I can provoke the SSS by rubbing the bottom on wool blanket.