Wireless: good signal but erratic speed

[Reuben D. Budiardja]

Hello,
I have two FC 4 machine with wireless card (one desktop, one laptop). The 
laptop use ndiswrapper. The wireless signal strength is reported good on both 
machines. iwconfig and kwifimanager reported it's above 90/100. But the speed 
are often erratic. Sometimes I got 11Mb/s, sometimes it drops to 1Mb/s. The 
access point is a D-Link combo wired+wireless router. Any idea what might 
cause this problem? Is this the AP problem or the machines ? I just don't 
understand why I get erratic wireless speed when the signal strength is 
reported good all the times. Thank you for any help.

RDB