Hi,
Nice to meet you!
There are 3 official solutions to help you connect Surface Pro 3 to the external monitor via HDMI connection:
- Surface Mini-DisplayPort to HDMI Adapter (The cheapest and most stable official solution)
- Surface Dock (The expensive yet multi-functional official solution)
- Microsoft Wireless Display Adapter (The most convenient official solution without HDMI cable required)
Alternatively, you can search for "Mini-Display port to HDMI Adapter" to see other vendors' products if you like. Certainly, it is recommended to use the official solution to ensure the compatibility. And there are other wireless display adapters on the market besides Microsoft's wireless adapter.
Thank You! :)