I have a trouble about my wireless router signal. My laptop is 25-30 feet (~8 meters) away from the router. There are two walls between them. Windows reports signal strength is two bars, and inSSIDer indicates the RSSI is about -77 to -80. The speed is good, YouTube works flawlessly, and I measured it reached the maximum bandwidth.
But periodically, the signal strength drops to -90 (according to inSSIDer) and of course the speed is horribly slow. Then it begins return to normal. It is weird; I don't change anything: the laptop position or even the lid. The router isn't hot and no one touches it. My sister checks Facebook and Twitter only so it's not like there is huge network burdens added. I also choose channel 8; my neighbors don't use it: I think no conflict here.
I search the internet and found a case like me here