Bochs is an open-source x86 emulator designed to emulate the x86 architecture in detail at the clock-level. Unlike QEMU, Bochs is slower but can be more accurate, making it suitable for research purposes or debugging low-level code. Bochs emulates older x86 processors, including i386, i486, and Pentium. This makes it suitable for emulating a processor as precise as the Pentium 100.