Some years ago I built my HTPC using a Zotac IONITX Mainboard with an integrated Atom 330 and it served me fine until now.
However as more and more of my Movies are H265 and/or 4K and I finally have an 4K TV I'd like to upgrade it to support those standards.
The integrated gpu is only capable of decoding h264 in hardware and can only output 1080p on HDMI and the integrated CPU is way to slow for software decoding of basicly any format with a resolution of more than 720p.
But it is more than fast enough to power kodi and never has more than 50% load during normal use.
I have a USB drive as OS storage and a passive CPU cooler / passive power adapter so it is 100% silent (media is on a nas).
I found the Nvidia GT 1030 to be capable of H265 hardware decoding and HDMI 2.0b output (4K), it is passive cooled, requires only 30Watts and is low profile (so it fits in my case).
However it has a PCIe 3.0 x16 adapter and my HTPC only features a PCIe 2.0 x1 Slot. I once read that physical slot and electrical bus width of PCIex do not need to match and PCIex 3.0 is backwards compatible with 2.0, so if I modify my Mainboard slot to allow the card to fit physically it should (at least in theory) work just fine, except for it being a bit slower.
But since there will be no 3D rendering and all data thats constantly transfered is the (encoded) movie stream I doubt that a 500Mbytes/s PCI lane would be a bottleneck.
So I'm pretty sure it will work and the card is only 70€ so not a big deal if it does not, but do I miss something important ?
Thanks in advance.