HD movies with Amazon Prime Video?

[jerwin]

I'm running Windows 10 on my 5k imac (2014). I believe that I've updated to the Anniversary Update.
Amazon Prime Viedo refuses to show me the HD stream for movies. Aggravatingly, this seems to a silent downgrade. I know that it's hopeless on mac os X, which is why I booted into windows in the first place.

Is there a browser I should be using? A plugin?

 

[jerwin]

Arcsoft bd and 3d assistant claims
Windows 10 Home YES
Intel Core i5-4690 3.5 Ghz YES
AMD Radeon R9 m290x (About 2048 MB) YES
graphics card driver 15.301.2101.0 NO
connector type Analog (Not HDCP Compliant) NO

so I probably need to update my driver. would be nice if I could do this through the normal amd channels, but, no...

 

[Gjwilly]

On the Mac and the PC both you should get HD as long as you use Chrome or else install the Silverlight plugin.
Unless your internet connection just isn't fast enough.

 

[jerwin]

ping 1 ms down 69.53 Mbps up 75.29 Mbps. Maybe that isn't sufficient for 1080p.

As for browsers, I've tried Edge, Firefox, Chrome, even Explorer.