So my iMac was having problems with poor Wi-Fi reception and completely lost Wi-Fi connectivity with the internal AirPort system. So I decided to try a USB WiFi antenna. I ordered these mainly because of the price. I wasn't expecting much but I was really surprised by the speed improvement. The first image shows the USB Wi-Fi adapter download speed at 85p Mbps. Second image showing iMac built-in Wi-Fi download at 57.4 Mbps. Big improvement! I used the Ookla SpeedTest app on a 27" iMac (Mid 2011) with 24GB or RAM and a 3.4GHz i7 processor. I used a short USB extension cable to raise the antenna above the iMac (third image).
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