Your monitor's aspect ratio is not 16:9, but 21:9. However, the standard Blu-ray or Ultra HD Blu-ray movie's aspect ratio is 16:9.

Not all of movies are 21:9 (1.35:1) recorded and then got re-encoded in standard 16:9 rectangular ratio by adding black borders on top and bottom sides.
Ultra HD Blu-ray movie would be played fine only if it is shot using 21:9 aspect ratio originally, or you will see black borders existing on the playback screen because of the physical aspect ratio difference.


Yep, 21:9 is a cinematic wide aspect ratio, but it is just a marketing-oriented and fancy feature rather than an useful design for monitors when you are "playing movies", because the standard and popular online video resolution is not 21:9.

To play 21:9 recorded movies on your 21:9 monitor, you can use one-click crop feature in powerdvd to crop the black borders, which are native planted in the movie video. It would make the center area of the video better fill the screen.
https://www.cyberlink.com/support/faq-content.do?id=21819

Quote Your monitor's aspect ratio is not 16:9, but 21:9. However, the standard Blu-ray or Ultra HD Blu-ray movie's aspect ratio is 16:9.

Not all of movies are 21:9 (1.35:1) recorded and then got re-encoded in standard 16:9 rectangular ratio by adding black borders on top and bottom sides.
Ultra HD Blu-ray movie would be played fine only if it is shot using 21:9 aspect ratio originally, or you will see black borders existing on the playback screen because of the physical aspect ratio difference.


Yep, 21:9 is a cinematic wide aspect ratio, but it is just a marketing-oriented and fancy feature rather than an useful design for monitors when you are "playing movies", because the standard and popular online video resolution is not 21:9.

To play 21:9 recorded movies on your 21:9 monitor, you can use one-click crop feature in powerdvd to crop the black borders, which are native planted in the movie video. It would make the center area of the video better fill the screen.
https://www.cyberlink.com/support/faq-content.do?id=21819

Thanks for taking the time to respond. Yep realised there would be black side borders in most films and programmes but for those films in the right aspect would be nice (6 underground streamed off Netflix looked very good on the HDR1000 FALD monitor I got less than half price used , couldn't stand more than 30mins of the film though....).

In the end though, the point seems to be moot. In researching this I discovered that Cyberlink enforces Intel SGX and I've got an AMD Ryzen CPU. I then looked into another UHD player and they don't enforce the CPU but only use the NVIDIA pipeline and I have a Radeon 5700....... All a bit silly really considering that probably the most common UHD capable player is the Xbox S (add the X to that too) which is AMD CPU and GPU albeit custom. Factor in that AMD actually has higher GPU share than NVIDIA (on account of their Integrated Grapics) and well.....

The PC option was a nice to have, not essential. Looks like I'll stick to playing my discs on the Xbox on the Telly.