สาย HDMI แพงๆ ช่วยให้ภาพดีขึ้นจริงหรือ?

## The Short Answer: No (Mostly)

HDMI is a **digital signal**. Unlike analog cables (VGA, RCA), there's no gradual quality degradation. It either works perfectly or doesn't work at all. A $5 HDMI cable produces identical picture quality to a $100 one.

## When Cable Quality Matters

The exception is **bandwidth certification**:

- A "High Speed" HDMI cable (10.2 Gbps) physically cannot carry 4K@120Hz
- An "Ultra High Speed" cable (48 Gbps) is required for HDMI 2.1 features

So the question isn't "expensive vs cheap" — it's "certified for the right speed."

## What You're Actually Paying For

Premium cables may offer:
- **Better build quality**: Braided jackets, reinforced connectors
- **Longer warranty**: 5-year vs 1-year
- **Certification testing**: Hologram sticker from HDMI.org

None of these affect picture quality.

## The $8 Rule

For runs under 3m, buy any certified Ultra High Speed HDMI cable for $8-15. For runs over 5m, invest in an active or fiber optic cable ($30-80). Never spend over $50 for a standard-length HDMI cable.