Cpuburn is is a set of programs that load x86 processor cores as heavily as possible for system testing. Instructions are run to maximize heat production, putting stress on the processor itself, the cooling system, the motherboard (especially voltage regulators), and power supply.
Before you begin, set up hardware monitoring. At a minimum you should be able to observe processor use and temperature in real time, and know what is your processor’s maximum rated temperature. Ideally you would also be able to observe system voltages in real time, and know what are acceptable values.
Linux users should be able to install cpuburn through the distribution’s package manager. The project website states that it also runs on Windows. I have no experience with this, and what follows assumes Linux.
The package installs several versions of cpuburn, each optimized for a different processor type. Ideally you would use the descriptions in man cpuburn of each program to select the most appropriate one for your processor; my experience is that burnMMX has worked well on every system I’ve used it on.
To use, simply run the program of your choice, one instance for each processor core, confirming in your hardware monitor that each core is fully occupied. Run for at least 10 minutes, ensuring that temperatures and voltages stabilize at acceptable values and that the system does not lock up. When finished, simply terminate the processes.
For example, to run burnMMX on each of my two cores:
$ burnMMX & burnMMX &
And to terminate them:
$ killall burnMMX
Not all systems have killall; make sure your does and it behaves as expected before relying on it.
If the processor overheats, see the cooling references, beginning with replacing your processor’s thermal paste. My experience with the cheap thermal paste available where I live is that it needs to be replaced every few years. If the system locks up — something I have no experience with — see the cpuburn references.
The Cpuburn project page at Freecode
The cpuburn package installs good documentation; begin with the cpuburn manpage and /usr/share/doc/cpuburn/README