Some people think it doesn't matter what type of HDMI cable you use and they'll all be the same, but not from what I've seen:
Originally Posted by r0ach
Yea, the Blurbusters guy says HDMI is better, but claimed the difference between the two should be impercetible, but that's definitely not my experience. The particular cables + different monitors I've tried and other various factors all play a part, but in my experience, on every monitor I've tested displayport seemed to give this inferior, more floaty cursor movemenet than HDMI I didn't like and also seemed to have higher latency.
It's a complex issue since I have like 4 HDMI cables in front of me and out of those I only like one cable (the thickest one go figure) with the others giving worse cursor movement. So things like the cables themselves also play a huge part. DVI seems like it was massively shielded with two chokes on each end, and HDMI and displayport seem like they have barely any shielding on them in comparison. I'm currently trying to figure out who makes the best HDMI cable that isn't some type of $100+ ripoff.
I think both HDMI and displayport likely lack shielding in general for standard consumer crap versions. The internal cables can even leak onto themselves. Nevermind the external factors. After reading the stupid 'electromagnetism' posts on this thread I've tested what happens when wrapping mouse cords around speaker magnets and things like that, and the only side effect I saw was dulled down and less responsive cursor movement and not even cursor skipping or anything, so having a poorly shielded HDMI or mouse cable probably does cause reduced responsiveness (but not the prime mover of the universe with Windows and BIOS settings having 0 effect as they claim).
To elaborate on the above topic, of the HDMI cables I have sitting around that I've tested, I have stuff like a skimpy Amazon basics cable, the HDMI cable that came with a Steambox/Alienware Alpha (it's the thickest), a Comcast HDMI 2.0 cable, and a few other mystery cables. All the skinny cables like the Amazon basics were inferior for cursor movement than the thick Steambox HDMI cable from Dell. They seemed like they had more of a deadzone or something where it felt less responsive.
The Comcast 4k res rated HDMI cable is thicker than the skinny Amazon basics one and didn't have the higher deadzone feel of the skinny cables and did feel responsive, but is for some reason more floaty and less precise than the even thicker Dell HDMI 1.4. Does the older 1.4 revision vs newer revision play a part in this? I dunno. But out of all these mystery cables the thickest one wins for mouse movement and it's an older 1.4 era cable (still works for 1080p at 144hz).
TLDR: Simply switching HDMI cables out of a grab bag has distinct effect on mouse movement with each one. I used to test this stuff back around 2004 when DVI cables were the standard and the differences in DVI cables seemed to be a lot smaller than what I see now with HDMI but you could still see some small differences there. The differences between HDMI cables are just way more pronounced. Not sure if it's solely due to cable thickness/shielding or if older vs newer 4k spec plays a part as well.