Current such PSUs will have a conventional normal molex connector (for legacy drives) and a SATA power connector, which is the one you need. The power supply we are talking about is any typical external supply that is used for powering HDDs and optical drives that would normally have been powered internally through a computer ATX supply. If I but an internal writer what all will I require to burn video files using it? I mean the hardware part? Thanks for taking time to write a detailed reply.
If you are using a laughtop with no extra SATA or eSATA port, then tough. So for me, the only reliable, predictable BD-R writer will be an internal writer, connected to a SATA port. This is not an issue with USB flash drives and HDDs but can be fatal when a BD-R writer's buffer underruns and produces beautiful coasters as a result. But lots of things can and often go wrong, or happens quite naturally, like the USB bus being polled while data transfers are taking place (when data is being written to a BD-R). In an ideal situation the USB chipsets should have the latest greatest drivers, and Windoze and all the programs that access other h/w through these ports should take advantage of that. This leads us to the other potential issue: the USB data bus itself. The Asus drive has an external power supply so it doesn't have to poach any from the USB port it's connected to.
I strongly discourage the use of BD-R writers of any ilk that is powered solely through a USB port (or two), no matter how convincing its ads and specs are and reviews are. Different computers react differently to over-current on a USB port some will cut power off, others will limit it to the maximum, others will also disconnect the data (and make the, gasp!, drive disappear). These writers in the thick and heat of recording a BD-R disc with motors and laser blazing away will consume lots of current that may faze some of these USB ports. Devices like USB flash drives (which consume little power) or others which just use the data bus can't reliably tell either way. However, there is no guarantee that actual USB ports on any computer can actually provide this much, or even if there is power from them at all. USB2.0 ports should be able to provide 0.5A maximum, USB3.0 0.9A. Some of these drives (like that Samsung) take power from the USB port itself.
There are two main issues with external BD-R drives: power source and the (USB) data interface itself.