Here's my situation. I currently have two computers with the Linksys Wireless WMP54G Wireless PCI-Adapters both wirelessly hooked up to a WRT54G (version 2.0). The computers with the WMP54G are located upstairs about 20 feet away from each other across the hall. The one with the router is located downstairs. One of the network adapters is a version 4.0 and the other is a version 2.0. The version 2.0 is an older one that I had bought a year ago that works perfectly fine with excellent signal strength and superb connectivity signals. However, I attempted to buy a new WMP54G for my other computer which is now a version 4.0. But it seems this one has massive connectivity issue. The minute I installed it, there was problems. It doesn't connect, and if it does, it takes a long time. When it does connect, it usually has "Very Low to Good" signal strength and the speed jumps from 54 Mbps to 48, to 36, to 24, to 11, and even sometimes as low as 1.1 or 5 Mbps. It's very strange because sometimes I get an okay connection, but it will jump to very low and becomes very irritating when trying to do anything. I currently use Windows XP Professional with the latest SP2 and all the updates. I have tried numerous solutions, and I am very desperate to get help. What is strange is the other computer across the hallway (still being upstairs and the router being downstairs from where my computer is having problems) which uses the same WMP54G, but an older 2.0 version is flawlessly fine. At first I thought it was my operating system being very buggy and unstable; so I reinstalled Windows XP Pro w/ the SP2 and the problem persisted. The next I thought that maybe where is gives a really bad signal perhaps b/c of a deadspot or something so I went out and bought the Linksys High-gain 7dbi antenna (model no. HGA7S). That did not work either. So I thought maybe I had a defective card so I went and traded in for another one which the problem still persisted. So I thought maybe it was a driver issue. So I updated the firmwire of my router to the latest official Linksys version, then tried the latest HyperWRT (stable version); I also updated the drivers of my WMP54G to the official latest version for the v4.0 of my PCI-card and then I tried to update it to the one found through Windows Update. I found no luck because the problems still persisted after upgrading both the router and the network card. Ultimately, I called Linksys and they advised me to changed around some of the settings in the admin panel through the Linksys webpage (http://192.168.1.1) and tweaked with the settings, switching the channels, and doing everything possible I could. After reformatting for another 5 or 6 times, I am where I am still at which is the problem still having crappy connection. Sometimes it connects, sometimes it doesn't. If it does, the signal is only 50-60% at NORMAL and will jump around to even lower giving me Very Low to Good (I can never get 4 bars or 5 bars--however the computer 20-30 feet away from mine across the other room on the same floor is always 95-100% signal strength and Very Good to Excellent). This is very, very frustrating for me because I think it is either ultimately my crappy computer, or something I am not doing right because the other computer works just fine. Anyone have any suggestions, please help!!! Thanks.