LG UltraFine & replacement Belkin USB-C cable gives blurry text

Question

I have an LG UltraFine 5K screen and a 2016 15-inch MacBook Pro.

The original USB-C cable that came with the screen broke. So I bought a Belkin USB-C replacement. Now all text is noticeable blurry. So it’s not fully compatible despite the fact that I bought everything directly from Apple.

Are there any settings I can try to tweak to get the same sharp text like with the original cable? I’ve already tried disabling font smoothing. If not, which cable I should buy to get full compatibility?

Answer 1

Looking at the specs of the the LG 5K Display and the accessories (cable) it comes with, you can't just use any plain USB-3 cable.

You need a Thunderbolt 3 Active Cable. Thunderbolt 1 and 2, natively, were active meaning power was required to operate properly. Normally, Thunderbolt 3 is a passive, meaning power isn't present. Any quality USB-3 cable will carry Thunderbolt 3 (and vice versa).

However, to drive this particular monitor, it appears LG requires an active cable.