Still having issues - tried everything

For the past month now, I have been having this issue and i've tried everything I can think of. Ever since I moved to a new place, my fps has dropped from the 40s range down to about 4-5fps. My first thought was bandwidth since i'm sharing the connection with two other people, but their connection is fine in SL and mine produces the same fps whether they are online or off (even when their entire computers are off!)

The only other thing I can think of is the router, which is a DLink, but there is no port forwarding or anything that I can find in the options.

ANY help would be really appreciated. As is, I can barely move let alone build or script (which is how I make my SL living) and forget flying around exploring anywhere. Any turning of the camera freezes me, sometimes to the point of having to relog or being bumped offline. I've called support twice, waiting over 20 minutes both times and ended up being asked to leave a message. Both times I did not receive a return call. I'm very very frustrated.

Edit: I should mention a few other things: I have tried changing the port that it logs in on. Also, all of my other stats are just fine. Bandwidth, user ping, packet loss... all of them are golden. Its just the FPS stat.

have you tweaked your sl graphic settings? they could b too high so to stress your card.

Yes, I turned all the bells and whistles off/down and still nothing. My computer is only a few months old. Here's the specs:
Pentium D CPU 2.80GHz
2.79 GHz, 1.00 BG of RAM
Microsoft Windows XP SP2
NVIDIA GeForce 7300

It was running fine before the move even with every feature turned on.

hmm i remeber reading about how dual processors would actually slow sl down.. do some research for such a topic..