Why Do 2 Laptops Show Completely Different Internet Speeds on the Same WLAN?

Question

I have 2 laptops at home, both on the same WLAN network. One (Dell laptop) runs on Windows 10 pro with Killer Wireless-n/a/ac 1535 Wireless Network Adapter; The other one (Sony Vaio laptop) runs on Windows 7 Home Premium with Qualcomm Atheros AR928X Wireless Network Adapter.

The Radio Type shows under the Wiressless Connection on Sony laptop is: 802.11n; The Radio Type shows on Dell laptop is 802.11ac

When I performed speed tests online, the two laptops resulted in completely different speed, the Dell laptop clocked around 150 Mbps consistently, the Sony laptop can barely get up to 50Mbps. I checked the Sony laptop's Wireless Network Adapter under Device Manager, it states: "the device is working properly."

Why do they result in such a huge difference? Is it because the Sony laptop's wireless adapter is too old?

Answer 1

Why do they result in such a huge difference?

WiFi is always promoted using ‘theoretical’ speeds and by this standard 802.11ac is capable of 1300 megabits per second (Mbps) which is the equivalent of 162.5 megabytes per second (MBps). This is 3x faster than the typical 450Mbps speed attributed to 802.11n.

Source 802.11ac vs 802.11n WiFi: What's The Difference?