Both ISA bus and PCI bus are suitable. Determine defects by difference sounds coding with build-in speaker It 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 codes Support 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 slot. Self checking remote display function Dual 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 system. Recall previous post codes at the touch of a button. Material: plastic colour: green Package Contents: 2 x PCI Analyzer Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.