My Lenovo Thinkpad E430 is running Xubuntu 12.04, and has been since April of 2013 (when I bought the laptop). For the past several weeks, my laptop has been freezing seemingly randomly. I started noticing it after installing and booting an older version of the kernel, but even after restoring to the most recent one, the problem still occurs, and so that may have just been a coincidence. The symptoms are as follow:
- Computer becomes completely unresponsive, include mouse cursor, et al., at random intervals. It can remain responsive for days at a time, or freeze multiple times in the space of an hour.
- Ctrl+Alt+F1 (or other consoles) do not work, or at least I can't switch to them.
- SysReq+REISUB seemingly does nothing.
- Any audio playing at the time will loop with a sample size of about a tenth of a second.
- Syslog and Dmesg contain nothing of note.
- After running memtest for over an hour, it found no errors.
Possible solutions are difficult to test since it can crash once every few days, or twice in the space of an hour. Leaving possible solutions indistinguishable from random chance.
It doesn't appear to be due to the CPU overheating, since I've had it freeze while sitting idle, and I've had it remain perfectly responsive while playing the multiplayer FPS Xonotic.
At this point, I've exhausted my troubleshooting skills, and am reaching out to the community. Thank you for any help you can provide.
Edit
Here is the output of lspci, in case the problem is a know issue with certain hardware or drivers:
00:00.0 Host bridge: Intel Corporation 3rd Gen Core processor DRAM Controller (rev 09)
00:02.0 VGA compatible controller: Intel Corporation 3rd Gen Core processor Graphics Controller (rev 09)
00:14.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB xHCI Host Controller (rev 04)
00:16.0 Communication controller: Intel Corporation 7 Series/C210 Series Chipset Family MEI Controller #1 (rev 04)
00:1a.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB Enhanced Host Controller #2 (rev 04)
00:1b.0 Audio device: Intel Corporation 7 Series/C210 Series Chipset Family High Definition Audio Controller (rev 04)
00:1c.0 PCI bridge: Intel Corporation 7 Series/C210 Series Chipset Family PCI Express Root Port 1 (rev c4)
00:1c.1 PCI bridge: Intel Corporation 7 Series/C210 Series Chipset Family PCI Express Root Port 2 (rev c4)
00:1c.2 PCI bridge: Intel Corporation 7 Series/C210 Series Chipset Family PCI Express Root Port 3 (rev c4)
00:1c.3 PCI bridge: Intel Corporation 7 Series/C210 Series Chipset Family PCI Express Root Port 4 (rev c4)
00:1d.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB Enhanced Host Controller #1 (rev 04)
00:1f.0 ISA bridge: Intel Corporation HM77 Express Chipset LPC Controller (rev 04)
00:1f.2 SATA controller: Intel Corporation 7 Series Chipset Family 6-port SATA Controller [AHCI mode] (rev 04)
00:1f.3 SMBus: Intel Corporation 7 Series/C210 Series Chipset Family SMBus Controller (rev 04)
02:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. RTS5229 PCI Express Card Reader (rev 01)
03:00.0 Network controller: Intel Corporation Centrino Wireless-N 2230 (rev c4)
0c:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 07)
Update 2
I've noticed that the crashes seem more likely early in the morning after the laptop sat unused overnight. Also, the crashes are more likely following a reboot, though I only reboot after a crash so it could be that the crashed just come in groups...
Update 3
I sent the laptop back to Lenovo to have the motherboard and RAM replaced, assuming that the problem was related to one of those two parts. Unfortunately, upon receiving my newly "repaired" laptop, the problem persists... I am beginning to suspect the HDD since that part was not replaced. I am going to test this by booting off of an external drive for a few days.
Update 4
After spending 24+ hours booting from an external HDD without a single failure, I've decided it is most likely to be the internal HDD (or maybe the SATA bus itself). I'm going to boot for 24 hours off of the internal HDD to be sure that the problem wasn't a software problem that corrected itself due to an update.
Update 5
It took several days of running on the internal drive for it to crash... I'm now going to run off an external drive again for a week or more.
Update 6
Well, it finally happened. It finally crashed while booted off of the external drive. Holmes never told us what to do when all possibilities have been eliminated, including the improbable.
Update 7
So far, I've been operating under the assumption that it's a hardware issue. At this point I'm going to try a different angle, and assume it might be a software issue. This article got me wondering if it may be a kernel issue: http://richxiong89.wordpress.com/2012/11/15/system-freeze-on-ubuntu-12-04-64-bit/
I've therefore updated to the 3.8 (3.8.0-37-generic) version of the kernel from Raring to see if it solves the problem. As always I'll report back soon.
Update 8
After running for 10+ days on the new kernel, I have yet to have my laptop freeze even once. At this point, it's most likely that the kernel's interaction with the hardware was to blame. I will be adding an answer defining what I did to install the newer kernel so that others who run into this problem will have a solution.
