Crashing Ever Odd half hour!.

Well here gos. Normaly i'm on the Release Candidate but since the last release for that it have gotten so dang laggy 5fps and avatars takes up to five minutes (if at all rezzing) before going from gray to actuly showing textures. So i thought what the hell.
I whent and installed the offical canditate (nOw before people scream Cache Conflict lets me put your mind to ease Release Candidate and Offical Client are useing seperate Cache Folders and not the same ones) But thing is on the Offical candicate i can be online about 30minute then CRASH BAM SMACK welcome to desktop please wait fiveminutes before loging back into SecondLag for another 30minutes of Lag before watching Desktop again.

Take a look at the posts in Internet DL and UL speeds???? I have been having the same problem for weeks, so maybe you can get some ideas from what people have been telling me to do...It would be nice if the info helped someone..hadn't helped me unfortunately.