I just upgraded from 100mbps to 500 mbps internet. All three of my Roku's have always tested at 85-95 mbps previously. Since upbrading my internet the tested speed on the Roku's has not changed, still between 85-95. Testing my speed on my pc's is 460+ mbps and wireless is at 300+ mbps. Although I dont have a streaming problem with the Roku I'm just wondering if this is a Roku hardware limitation or something else.
Your suspicion is correct. Roku uses "Fast Ethernet" 10/100 Mbps ports, not "Gigabit Ethernet" 10/100/1000 Mbps ports. High 80's/Low 90's is about all you can squeeze out of a 100 Mbps connection. This is more than adequate for streaming a single stream at a time over the internet.
The Roku devices (when wired/using ethernet) are capable of Fast Ethernet. (max transmission rates 100 mbps).
If you connect wirelessly/wifi to your Ultra and other ethernet capable Roku devices, you should see the higher speeds of your new internet reflected. (Settings/Network/Check Connection)
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As a sidenote, assuming you meant Premiere+ (4630), rather than Premium+.
