Recently I have purchased Dell Venue 11 pro 7140, running Windows 8.1. So far it had continuous issues with Wi-Fi connections: often it gets limited, and the only thing which helps is to disable\enable wifi adapter or restart. During one of the restarts I went to BIOS and noticed, that WiFi adapter is not recognized at BIOS level at all.However, after shut down and starting the tablet again it appeared. That happened many times; during this issue windows does not find the adapter in device manager either. Please see the picture attached. I have updated Dell WiFI drivers,BIOS, and Chipset drivers, but this did not help
Welcome to the Dell Community @mumarmasood
Try updating the Network drivers.
Drivers for your Venue 7140 Pro: