For HDMI 2.0. For HDMI 2.1 and 4K/120hz you're looking at north of $25 and don't get VRR support.
Fair enough about VRR, but £13 for 4k/240Hz - https://www.amazon.co.uk/dp/B0FQCF62CD
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Fair enough about VRR, but £13 for 4k/240Hz - https://www.amazon.co.uk/dp/B0FQCF62CD