Both ISA bus and PCI bus are suitableDetermine defects by difference sounds coding with build-in speakerIt can diagnosis the motherboard signal which show the problem of CPU, Memory, video card, etc The POST code display is made up of a dual, dot matrix hexadecimal read-out that display's Power On Self Test (POST) status codesSupport the power source working indicator -- +5V, +12V, +3.3V and 12V (When indicator LED is on to indicate its respective power is fine, otherwise to indicate its respective power is failure.)Fully compatible with any kind motherboards which has the PCI and ISA bus slotSelf checking remote display functionDual POST code display - User can readout the POST at PCB component and solder side. It is easy to view the POST code when user plugs the POST card in computer systemRecall previous post codes at the touch of a buttonColor: As the pictureSize: Approx. 8.9 x 8.3 x 0.2cm (L*W*H)1 x Main diagnostic card1 x Ribbon cable1 x English Manual