In a terminal: sudo -s echo l > /proc/sysrq-trigger dmesg
At the end of the dmesg output, you should have a short section that says "NMI backtrace" for each of your CPU cores. Look for any messages at the end of the backtrace sections to give you a clue as to whether you have some process that's malfunctioning.
In the example on the askubuntu.com page you linked to, the poster had a malfunctioning kernel module for his Intel ethernet port ("e1000e" is a Linux kernel driver for Intel network adapters). Therefore, he had a series of "e1000e" messages at the end of his backtrace section on dmesg.
If you copy and paste your backtrace section at the bottom of the demsg output, we may be able to help you.
