I believe a lot of people facing the problem of the Adobe Dreamwaver 3 are use up a lot of your CPU resources, eventhough you are not actually open a lot of file in the Dreamwaver.
I try to find a lot of crack to get the issue solve but no luck until I finally found it from one of the forum via Google.
What you need to do it just download the crack from this link and replace the Dreamwaver.exe in your installation folder. Remember to turn off your dreamwaver when you try to replace the file, then just try to open up your dreamwaver and see.
Click here to download the patch