Abstract: A book-style computer attachable to an LCD monitor has a locking portion in conformity with the VESA (Video Electronics Standards Association) standards such that the book-style computer is attachable to the backside of a generic LCD monitor. The book-style computer is comprised of a front lid, an operation portion, a rear closure, and a heat-dissipation portion, and is characterized in: all the through holes being in conformity with the VESA standards to allow the computer to be fixed in the backside of the LCD monitor, and the heat-dissipation portion further comprising a bottom plate, a leaf-style heat sink, and a laterally blowing fan. A CPU main board is characterized in that a heat generation unit is attached on the bottom plate of the leaf-style heat sink while other components are installed on the other side of the CPU main board.