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Yesterday I was given my brother's old laptop - core i7, 2.67GHz, 8GB RAM, 128GB SSD, Win7 64 bit. It's a Sony Vaio Z11. Approx 18 months old.

When running something computationally intensive, the fan starts up and after about 30 secs it just powers itself down with no warning. I guess it is overheating. There is nothing in the event logs to suggest what is causing it - the only thing I see is "the last system shutdown was unexpected" or something similar. This is a problem for me because I use a lot of number crunching apps, which pretty much makes it useless to me. I would like to know if there is anything I can do, other than the obvious things I've done already - open up and clean out dust, re-install the OS. According to my brother, this problem started about 6 months ago when it was already outside warranty. If it's just used for simple things - web browsing, word processing etc, the problem does not occur. Any ideas for what I can do to fix this ?

Update: I found that the laptop has 2 hardware settings for graphics: Speed and Stamina - the Speed setting seems to use an nvidia GEforce GT 330M, while the Stamina setting uses an Intel chipset. With the setting on Speed, I can hear the fan the whole time, and the system powers down after a short while (5-10 mins) even just doing basic tasks (browsing this site for example), but doesn't shut down if I just leave it switched on. In this mode it also sometimes just freezes the screen and I have to power off myself. However on Stamina setting it only powers down when doing number crunching and never freezes the screen.

Update2: I took the laptop to a repair centre and they say they "professionally cleaned out dust" and "removed heatsinks, cleaned old thermal paste, applied new thermal paste and reseated the heatsinks". They say they couldn't find anything wrong with it. The problem has improved in the sense that it now runs for about 3 mins instead of 30 secs before shutting down. I have installed Everest Home edition which shows that one core of the CPU (HTT unit #1) stays at 0% while the other 3 cores are at 100%. I thought this was a bit strange. I tried to post a screencapture of this, but it said "We're sorry, but as a spam prevention mechanism, new users aren't allowed to post images. Earn more than 10 reputation to post images." On a related note, I wonder why my question gets so many downvotes ?

share|improve this question
18 months sounds like it may be within warranty - get sony to fix it up – Journeyman Geek Jun 24 '12 at 7:27
@Journeyman Geek thanks but it had a 1 year warranty, and it was also bought in Hong Kong by my brother when he was working there, and Sony Europe won't support it because he had not paid extra for an international warranty – Joe King Jun 24 '12 at 10:35
It doesn't sound like overheating, but have you tried a replacement heatpipe/heatsink? Occasionally the heatpipes will fracture (good luck seeing the crack), making them almost useless for moving heat away from the chips. Aside from over-heating, have you done disk checks? Have you tried long term RAM tests (48hours+) and/or replacement RAM modules? – Ƭᴇcʜιᴇ007 Jul 7 '12 at 19:38
@techie007, thank you, yes, as per my Update2 the repair shop told me they "removed heatsinks, cleaned old thermal paste, applied new thermal paste and reseated the heatsinks". They also said they ran some diagnostic checks but "couldn't find anything wrong with it". Can you recommend any software to run the checks you mention ? Also please note the disk is an SSD (90% full at present). – Joe King Jul 10 '12 at 7:20

You won't get an event log warning if the laptop shut down due to BIOS intervention, which is usually due to overheating. The OS isn't shut down cleanly, the BIOS just cuts power to everything and stops the CPU.

If this was a desktop I'd suggest it is a power supply issue or maybe the thermal paste/heatsink needs to be reapplied to the CPU.

Check the BIOS on the off chance a shutdown temperature can be set. This isn't likely, especially on an OEM system.

Do apply any BIOS updates as they contain microcode updates for the CPU sometimes and that may help.

Really though it is sounding like one of the below is the cause:

  • Laptop has been exposed to physical damage of some sort (dropped, etc.)
  • Laptop has been exposed to extreme heat (left in sunlight in car, run in a carrying case, etc.)
  • Laptop has gotten moisture on it somehow (you can look for corrosion on the battery connector and inside if you take the bottom off)
  • Dust has accumulated deep inside the machine - you may need to take it apart and dust it
  • Long shot, but possibly some removeable hardware is defective such as RAM, the optical drive, or possibly the hard drive.
share|improve this answer
Yeah, I would try repasting the CPU/GPU. It's not an easy task on some laptops, but may fix your problem. If it doesn't, then yeah some component on the mainboard is probably damaged. – Adam Jun 24 '12 at 5:43

Typical summer problem. Basic maintenance solves this:

  1. Clear dust with vacuum cleaner
  2. Set power management options to extended battery life preset, will also lower CPU cycles thus slowing up high temperature buildups
  3. Install BES or some similar CPU limiter
  4. Either buy (or improvise) an external cooling solution
share|improve this answer
Thanks, but as I said, I cleaned out the dust already (first thing I tried). The second thing I tried was a clean install of the OS. The first number crunching app I install (maple, matlab, mathematica, R) will create the problem. The problem occurs whether or not it is plugged into a power source or running on batteries and I have played with the power management options, with no effect so far. I already have a plinth with fan which the laptop sits on when on my desk. It seemed to have no effect. I haven't tried the 3rd option yet, but limiting CPU cycles seems to defeat the object... – Joe King Jun 23 '12 at 22:14
... of what I am trying to do (a lot of number crunching).. – Joe King Jun 23 '12 at 22:14
I am new here and it would be great if someone can tell me why I get downvoted. – Joe King Jun 23 '12 at 22:16
The other thing is.... I don't think it's a "typical summer problem" because, as I said in the OP, the problem started 6 months ago, in the middle of winter. – Joe King Jun 23 '12 at 22:17
There are CPU/temp/performance monitors available. Run one of these while you startup a calc and you'll see if there's a temperature problem related to CPU usage. Also, try running a memtest utility and see if it dumps. There are various extended benchmarking/testing apps avail. Norton is a commercial source that comes to mind, but I think Phoronix has a test-suite also. – glallen Jun 23 '12 at 22:27

Sometimes thermal management on laptops requires BIOS updates, specific drivers and software. So go down that list at the Sony site for your specific model.

  1. Get and install latest BIOS.
  2. Same for drivers/software (the software list for Vaio laptops is LONG but most are needed to get all features working).
  3. Try the Sony recommended/provided display drivers first.
  4. Test again and try latest graphics drivers if adventurous but be prepared to revert back to recommended/provided drivers.
share|improve this answer
Thank you. After I re-install the OS and update/patch the OS, the "vaio update" utility then downloads the latest BIOS and drivers from sony automatically. I'm not sure what else I can do in this regard ? – Joe King Jun 24 '12 at 7:00

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