This time you won't have to care how much free time your real CPU's cores have, because DOSBox will always use 100% of your real CPU's one core. The DOSBox window will display a line 'Cpu Speed: max 100% cycles' at the top then. You can also force the fast behavior by setting cycles=max in the DOSBox configuration file. DOSBox can use only one core of your CPU, so If you have for example a CPU with 4 cores, DOSBox will not be able to use the power of three other cores. Once 100% of the power of your computer's real CPU's one core is used, there is no further way to speed up DOSBox (it will actually start to slow down), unless you reduce the load generated by the non-CPU parts of DOSBox.

You can see how much free time your real CPU's cores have by looking at the Task Manager in Windows 2000/XP/Vista/7 and the System Monitor in Windows 95/98/ME.

In this mode you can reduce the amount of cycles even more by hitting CTRL-F11 (you can go as low as you want) or raise it by hitting CTRL-F12 as much as you want, but you will be limited by the power of one core of your computer's CPU. If you for example set cycles=10000, then DOSBox window will display a line 'Cpu Speed: fixed 10000 cycles' at the top. You can force the slow or fast behavior by setting a fixed amount of cycles in the DOSBox's configuration file. But you can always manually force a different setting in the DOSBox's configuration file. How to speed up/slow down DOSBox CPU Cycles (speed up/slow down)īy default (cycles=auto) DOSBox tries to detect whether a game needs to be run with as many instructions emulated per time interval as possible (cycles=max, sometimes this results in game working too fast or unstable), or whether to use fixed amount of cycles (cycles=3000, sometimes this results in game working too slow or too fast).

Cycle sounds magic box