Microsoft is now rolling-out firmware updates for Surface 3 and Surface Pro 3. The Firmware updates bring many new features and fixes along with some update Intel HD Drivers. This is how you can update manually.

Step 1:Go to Start Windows logo, and select Settings > Update & security > Windows Update.
Step 2:Select Check for updates. If updates are available, they will install automatically.You may need to restart your Surface after the updates have installed.

Check below for detailed changelog for both Surface 3 and Surface Pro 3.

Surface 3 Changelog:

January 2016 updates

The following update will be listed as “System Firmware Update – 1/19/2016” when you view your update history.

Note
When Surface updates are provided via the Windows Update service, they are delivered in stages to Surface customers. As a result, not every Surface will receive the update at the same time, but the update will be delivered to all devices. If you have not received the update then please manually check Windows Update later.
  • Surface System Aggregator Firmware update (v1.0.51500.0) improves reliability with the Surface 3 Type Cover
  • Surface UEFI update (v1.51116.18.0) adds ability within Windows Power & sleep settings to turn off Wi-Fi during sleep. Improved touch support for UEFI menus and support for 3rd party onscreen keyboards improvements.
  • Microsoft Surface ACPI-Compliant Control Method Batter driver update (v1.2.0.2) ensures correct surface driver is installed.
  • Wireless Network Controller and Bluetooth driver update (v15.68.9037.59) improves access point compatibility and throughput on 5GHz.
  • Surface Digitizer Integration driver update (v1.0.1.1) improves pen pairing feature with newest surface pen.
  • Surface Pen Pairing driver update (v1.0.1.1) improves pen pairing feature with newest surface pen.
  • Audio Device driver update (v604.10135.7777.2109) improves audio quality with some applications.
  • I2S Audio Codec driver update (v6.2.9600.527) improves audio quality with some applications.
  • Serial IO GPIO Controller driver update (v604.10146.2652.3930) improves system stability and touch screen reliability.
  • Dynamic Platform & Thermal Framework Driver update (v604.10146.2651.1559) improves system stability and touch screen reliability.
  • Serial IO I2C ES Controller driver update (v604.10146.2654.3564) improves system stability and touch screen reliability.
  • Serial IO SPI Controller driver update (v604.10146.2657.947) improves system stability and touch screen reliability.
  • Serial IO UART Controller driver update (v604.10146.2653.391) improves system stability and touch screen reliability.
  • Sideband Fabric Device update (v604.10146.2655.573) improves system stability and touch screen reliability.
  • Trusted Execution Engine Interface driver update (v2.0.0.1067) improves system stability and touch screen reliability.

In addition to the updates list above, the following additional updates are available for Surface 3 (AT&T 4G LTE), Surface 3 (Verizon 4G LTE), Surface 3 (4G LTE) in North America (non-AT&T), Surface 3 (4G LTE) in Europe and Surface 3 (Y!mobile 4G LTE):

  • GNSS Bus Driver update (v20.23.8244.18) improves GPS experience.
  • GNSS 47531 Geolocation Sensor driver update (v20.23.8244.18) improves GPS experience.
  • Surface CoSAR driver update (v2.0.304.0) enhances the Wi-Fi connectivity reliability while mobile broadband is ON.

In addition to the updates list above, the following additional update is available for Surface 3 (Verizon 4G LTE):

  • Surface IA7260 Firmware Update (v1544.01.00.28) improves mobile broadband network stability.

Surface Pro 3 Changelog:

January 2016 updates

The following update will be listed as “System Firmware Update – 1/19/2016” and “Intel Corporation driver update for Intel(R) HD Graphics Family” when you view your update history.

Note
When Surface updates are provided via the Windows Update service, they are delivered in stages to Surface customers. As a result, not every Surface will receive the update at the same time, but the update will be delivered to all devices. If you have not received the update then please manually check Windows Update later.
  • Surface Pro Embedded Controller Firmware update (v38.9.50.0) improves system start-up reliability.
  • Surface Pro UEFI update (v3.11.1150.0) adds pen support in UEFI menus and improved support for 3rd party onscreen keyboards.
  • Surface Fingerprint Sensor driver update (v2.2.10.6) improves accuracy.
  • Wireless Network Controller and Bluetooth driver update (v15.68.9037.59) improves access point compatibility and throughput on 5GHz.
  • HD Graphics Family driver update 4331 (v20.19.15.4331) improves color calibration and system stability.
  • Display Audio driver update (v6.16.00.3189) supports compatibility with the updated HD Graphics Family driver.
  • Surface Cover Audio driver update (v2.0.1220.0) improves system stability.
  • Microsoft Surface ACPI-Compliant Control Method Battery driver update (v1.2.0.2) ensures correct surface driver is installed.

Source