Compared to its predecessor, the Raspberry Pi 2 Model B, it has a more powerful Quad Core Broadcom BCM2837 64-bit ARM Cortex-A53 processor running at 1,2 GHz (while the Pi 2 used Quad Core Broadcom BCM2836 32-bit ARM Cortex-A7 processor at 900 MHz). It also features Bluetooth Low Energy (BLE) as well as a built-in BCM43143 WiFi chip, which means no external WiFi adapters are needed. It has improved power management with switched Micro USB power source supporting up to 2.5 Amps allowing you to connect even more powerful external USB devices to your Pi. A minor change is that the micro SD card slot is now push-pull rather than push-push type.
Like the Pi 2, it has:
- 4 USB ports,
- 40 GPIO pins,
- Full HDMI port,
- Ethernet port,
- Combined 3.5mm audio jack and composite video,
- Camera interface (CSI),
- Display interface (DSI),
- Micro SD card slot,
- VideoCore IV 3D graphics core.
The Raspberry Pi 3 has an identical form factor to the Pi 2 (and Pi 1 Model B+). All the connectors are the same as those on the Pi 2 making it fully compatible with older accessories. The only difference is that the LEDs are on the other side of the board with WiFi module taking their place. Thus, they may not be visible in non-transparent Pi 2 cases.