Hardware Bottlenecks — Why Your Wi-Fi Caps Your Speed, Not Your Plan

This is the most important networking lesson I’ve learned: your internet plan is never the bottleneck if you’re on Wi-Fi.

I proved this to myself by switching from Simba 10Gbps to Singtel 2Gbps. The speed was identical — ~270 Mbps in both cases. Not because the plans are the same, but because my laptop’s Wi-Fi card hit its ceiling at that speed and couldn’t go higher regardless of what the ISP was offering.

The Throughput Chain

Every byte you download travels through a chain of links. Your connection is only as fast as the slowest link in that chain.

The slowest link determines your speed. If that’s your Wi-Fi (288 Mbps PHY), you’ll get ~270 Mbps regardless of whether your plan is 2 Gbps or 10 Gbps.

Why Wi-Fi Is Always the Bottleneck

Wi-Fi is shared, half-duplex, and susceptible to interference. Even with Wi-Fi 6:

Wi-Fi Generation	PHY Rate (2 streams)	Real Throughput	Bottleneck vs 1 Gbps Plan
Wi-Fi 4 (802.11n)	300 Mbps	~150 Mbps	Severe
Wi-Fi 5 (802.11ac)	867 Mbps	~400 Mbps	Significant
Wi-Fi 6 (802.11ax)	1.2 Gbps	~600 Mbps	Moderate
Wi-Fi 6E	2.4 Gbps	~900 Mbps	Mild
Wi-Fi 7	2.9+ Gbps	~1.5+ Gbps	None (for now)

My laptop has a Realtek RTL8852BE (Wi-Fi 6, 2×2 MIMO, 80 MHz channel). At -65 dBm signal: - Theoretical PHY: 288 Mbps - Real throughput: ~270 Mbps

Ethernet — The Forgotten Option

Plug in a cable and the picture changes completely.

I ran a test on my machine: - Single-stream Wi-Fi: ~147 Mbps - Multi-stream Wi-Fi (3 streams): ~273 Mbps - Gigabit Ethernet: ~940 Mbps (theoretical, if I had a cable)

The difference isn’t the plan — it’s the medium.

The Real Test: Saturation

To find your true max, run parallel downloads. A single TCP stream might not saturate the link:

# Run 3 parallel downloads from a fast server
for i in 1 2 3; do
  curl -o /dev/null -s \
    http://speedtest.singapore.linode.com/100MB-singapore.bin &
done
wait

On my machine, this hit ~273 Mbps total — the Wi-Fi link was fully saturated. No single-stream test could achieve this because TCP overhead and Wi-Fi’s half-duplex nature limited each stream.

What This Means

If you’re on…	Your max real speed	Upgrade to 10Gbps?
Wi-Fi 5	~200-400 Mbps	Won’t help
Wi-Fi 6 (2 streams)	~500-600 Mbps	Won’t help
Wi-Fi 6E	~800-900 Mbps	Would help slightly
Wi-Fi 7	~1.5+ Gbps	Would help
Gigabit Ethernet	~940 Mbps	Would help
2.5 GbE Ethernet	~2.3 Gbps	Would help

If you’re on Wi-Fi 6 or older, switching to a faster plan changes nothing. The bottleneck is the wireless link, not the subscription.

The only practical ways to get more speed: 1. Get closer to the router (better signal = higher PHY rate) 2. Use Ethernet (USB-C adapter is ~$15) 3. Upgrade to Wi-Fi 7 (requires new laptop and new router)

For most people on Wi-Fi, the cheapest 10 Gbps plan is as fast (and as slow) as the most expensive one. Don’t let the marketing fool you.