 purplecrl Installed the drivers then put the laptop to sleep manually. Resolved
Brand new Inspiron 15 3525 laptop. When waking from sleep, the WI FI is only 20mbps. Reboot and it goes back to 220-240mbps. Uninstalled the "Smart Byte" app. No change. 
Inspiron 15 3525 very slow Wi-Fi after waking from sleep