I have had a custom built PC for about a year, and recently I've been experiencing a problem with the Wifi connection. Previously the Wifi would connect to my network but disconnect as soon as I attempted to use it. Presently the problem is different. Rather than disconnecting, the Wifi stays connected, but delivers incomprehensibly slow speeds. A problem with my wifi card has most likely been ruled out as I upgraded the card from an Asus PCE N-15 to a Rosewill RNX-AC1900PCE about a week ago and the problem had not changed. Any help is much appreciated, thanks much!