Is It Your WiFi or Your Computer? How to Tell the Difference
Slow internet is frustrating — but is it your router or your computer? Here is a simple way to work out exactly where the bottleneck is before you call your broadband provider.
Test your speed at the router first
If possible, connect a device directly to your router with an ethernet cable and run a speed test at speedtest.net. This bypasses your WiFi entirely. If you get your full contracted speed via ethernet but slow speeds over WiFi, the problem is your WiFi signal or your computer's WiFi adapter — not your broadband connection.
Test on multiple devices
Run a speed test on your phone over WiFi and on your computer over WiFi at the same time. If your phone gets fast speeds but your computer does not, the problem is specific to your computer — either its WiFi adapter, its network settings, or background processes consuming bandwidth.
Check what is using your bandwidth
On Windows, open Task Manager and click the Network column to see which programmes are using the most data. On Mac, open Activity Monitor and click Network. Large Windows updates, cloud backups (OneDrive, Dropbox, Google Drive), and video streaming in background tabs are all common culprits that consume bandwidth silently.
Common computer-side WiFi problems
Driver issues are a frequent cause of poor WiFi performance on Windows computers. Go to Device Manager, find your network adapter, right-click and select Update Driver. Also check your network adapter's power settings — Windows sometimes reduces WiFi adapter power to save battery, which reduces performance even when plugged in.
When to contact your broadband provider
If all your devices are slow whether connected via ethernet or WiFi, and the problem persists at different times of day, contact your broadband provider. Ask them to run a line test — they can often identify issues with the line between your home and the exchange that would never show up on your devices.
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