Are you confused by the throughput speeds claimed by routers and powerline adaptors? Let our Helproom Editor explain how to measure your network's speed. See also: Set up powerline networking adaptors.

QUESTION: I have a Wireless N150 modem router to which I wirelessly connect two laptops, plus a desktop PC via 200Mbps powerline adaptors. The software supplied with the adaptors shows them to be running at 195Mbps. How can this be possible if my router has a maximum speed of 150Mbps? My broadband download speed is around 5.5Mbps; why is this so much slower?

HELPROOM ANSWER: Your modem router is simultaneously using three types of connection, each of which has a different maximum speed.

The N150 specification refers only to the maximum speed of your Wi-Fi network and isn't related to the performance of your broadband connection or powerline adaptors. It will therefore determine the maximum data-transfer speed between wireless devices connected to your router.

Each of your powerline adaptors will be connected directly to a wired network port: one on the router and another on your desktop PC. These ports have their own maximum speeds. ADSL routers are often limited to 100Mbps, although some support 1,000Mbps, which is the highest offered by most modern PCs.

Although the connection is reported as 195Mbps, you'll probably be achieving a considerably lower throughput via this connection – not that it matters, because your desktop won't be able to communicate with your laptops any faster than the maximum speed of the wireless connection, which itself will be slower than the theoretical 150Mbps it claims.

Furthermore, all your PCs will be limited by your broadband speed rather than your home network performance when it comes to accessing the internet.

The speed of your broadband connection is determined by the technology used by your ISP (most likely ADSL2+), the broadband package you're signed up to, the distance to your local exchange and the quality of your telephone line.

To measure your broadband speed, visit

See all How to articles. Get free tech support in the Helproom Forum.

Visit Windows 7 Advisor for more Windows advice. Or email our Helproom Editor for bespoke advice.