So in a nutshell. I made a 4K timelapse that I would like to play on a HTPC. I have a successful build on a simple i3 3220 (ivy), Sapphire 7750, Dual channel 1600, and a fast raid0 2x SSD setup sata3. It plays on a 4K tv without issue. It's an uncompressed AVI so it needs SSD speed but not really CPU or GPU power. I've also made it work on a Dell 8500 from 2012 with similar specs (it might have a Sandy but not sure?).
So my question is when trying to make my older systems play the same file with the same SSDs (actually 3 SSDs because of sata2), memory, & video card it fails. I have only tried my older i7 920 on an x58 ASUS MB but it's not even close to making it work. What in the ivy CPU makes 4K playable or are there other older CPUs intel or AMD that might work as well? I know that Intel says Ivy is the first to support 4K so does that mean that nothing else will? What is special in the Ivy (or Motherboard chipsets) that make 4K playback possible?