Airport Reception reduces to 2 bars.

[HannahBiafra]

Hey there,

My iMac has been perfect up until this point.
I connect to my WiFi, and it is fine for about a minute. It then goes down to two bars and runs very slowly.
Every other computer in the house runs fine and no one else is downloading anything
I have rebooted both my iMac and the router/internet several times and nothing seems to be making a difference.
Help!

 

[djackmac]

It would be nice to know the distances of all computers including obstructions like walls, floors, material of each from the wireless access point. Plus you need to check for interferences from other equipment that might be next to the iMac.