The issue I am having is with my paid IPTV service, using IPTV Simple Client (or even when playing channels directly from the addon). The service works, but playback is not smooth. I have no issues playing media streamed from a shared drive in my windows network.
Unfortunately I don't use IPTV so can't help with this issue
The display driver support isn't great for these old cards (especially the nvidia motherboard chipsets with integrated graphics) and may have some quirks (I know I still get around 15-30 dropped frames per movie on my 8100) .
A different driver branch may help such as the v173.14.39 but will likely need many patches to compile for use with modern Linux kernals.