Fix
Hitomi Heron(and anyone else who might have the same problem I had),
A friend of me found a simple fix that you need to do everytime when starting up Second Life.
Whenever you start it up you just wait for it to get into the login screen, then you press ctrl-shift-escape to open up 'Task-Manager'. There should be a few tabs on the top of which one is called 'Processes', Click this one and look for the Second Life viewer process. Right click on it once you found it, and select the affinity option and a new screen should pop-up in which there are several processors selected. Deselect all but one, and now Second life should run smooth if you have the same problem as I had..
It really worked well with me, I now got the Hz that I usually have with other games and programs.