Question HDMI cable problem

[mwalimu]

My setup: I have a Win10 laptop with an HDMI port. Sometimes I take it to my living room and plug it into one of the HDMI ports of my widescreen TV, which Windows recognizes as a second display, and watch videos (using VLC or at various websites that can play videos in fullscreen mode). I've been using this setup (same TV, same laptop) for more than 4 years and it's worked great. A couple of weeks ago I accidentally damaged the HDMI cable (which is 15' long); it still works but I'm not sure I trust it and figured a longer cable would be better anyhow, so I ordered a new 25' cable.

The new cable arrived and... It doesn't work. When I plug it in, on the TV I see the wallpaper and taskbar like I'm used to, for about 1-2 seconds, briefly see some lines of static across the screen, then it goes black. After about 10 seconds it pops up again for just a couple of seconds like before, goes black again, and keeps repeating this behavior in a loop.

Things I've tried that didn't work (same behavior as above):

• wiggling and reseating the HDMI cable at both ends;
• plugging the HDMI cable into the other two ports on the TV that are normally connected to my Blu-ray player and my cable box;
• changed the refresh rate under advanced display settings from 29.970 Hz to 23.976 Hz.

Everything goes back to normal and works as before when I revert to using the old cable.

I tried replacing the cable connecting the Blu-ray player to its port with the new one, and the Blu-ray player and all its on-screen menus worked fine. (Interestingly, even though both devices were powered off while I was replacing the cable, the TV detected that a "new" device was plugged in, even though it was actually the same device as before and only the cable was new. I wonder if the TV when powered off is still "awake" enough to detect when cables are plugged and unplugged, and wouldn't have detected it if I'd fully cut power to it instead of just using the off button.)

Considering this setup has worked for 4 years and all I did was replace the cable, it seems unlikely that it's anything to do with my Windows settings, but I suppose that's slightly possible. Could it be a microsecond timing issue that isn't a problem with a 15' cable but is with a 25' cable? Could some arcane display setting (besides the refresh rate change noted above) or a driver update make a difference? Both the old and new cables are HDMI 2.0 and rated for 4K (see links below if you want to look up more details). Anything else I should try before I RMA the cable?

It would also be nice to know if the cable is actually defective, or simply the wrong cable for the job (such as if there's a maximum usable run length that the longer cable exceeded).

Thank you for any assistance you can provide.

Newegg catalog pages for the HDMI cables:
New: https://www.newegg.com/black-link-depot-25-ft-hdmi-cables/p/N82E16812189136
Old: https://www.newegg.com/black-link-depot-15-ft-hdmi-cables/p/N82E16812189055

mwalimu

 

[NedSmelly]

I’d return that cable for an HDMI 2.1 certified one - especially at that length.

 

[dwd999]

IDK for that length I would probably get an active chipset cable like:

https://www.monoprice.com/product?p_id=12959

 

[mwalimu]

Thank you to those who responded. I have ordered an active 2.1 cable and will be returning the one that didn't work.

 

[mwalimu]

Today I received the 2.1 active cable (30'). It worked!

Now that I have a known working cable, I can try harder to bend the old damaged cable back the way it was. If it works, I'll put it in my laptop bag and may use it when I travel.

When I RMAed the 25' cable, Newegg gave me the refund and told me I didn't have to return it. Not sure what I'll do with it. When researching HDMI cable types, multiple sources indicated that passive cables should usually work up to about 10m (32') in my situation, so apparently my laptop HDMI port puts out a weaker signal than most. Also noted that the 25' cable was noticeably thicker than the old 15' cable, suggesting that the 25' may have used heavier gauge wire. Could that have been a factor?