Laptop-to-TV cables: what 4K 120Hz actually requires
Getting 4K 120Hz from a laptop to a TV depends on the ports at both ends, not just the cable. Calculating bandwidth per resolution shows exactly where 18Gbps and 48Gbps diverge.
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#HDMI 3 posts
HDMI 2.1 vs DP 2.1: The Bandwidth 4K 240Hz Actually Needs
HDMI 2.1's 48Gbps shrinks to 42.6Gbps once encoding overhead is stripped out. Here is the bandwidth 4K 240Hz at 10-bit really demands, calculated line by line against every standard.
HDMI 2.1 vs 2.0: 4K 120Hz, 8K and Choosing the Right Cable
To run 4K 120Hz gaming, 8K or VRR you need HDMI 2.1 — and a certified Ultra High Speed cable. Bandwidth is 18Gbps versus 48Gbps. Here is the required bandwidth computed by resolution and refresh rate.