Don't need anywhere near that much. On this 2012 PC with 32GB of RAM I have 3300 tabs open in Chrome and 3100 in Firefox. Plenty of RAM left over for other things too. I use The Marvellous Suspender for Chrome and Auto Tab Discard for Firefox to keep the memory and CPU use down. Session Buddy for Chrome makes it easy to manage them. I don't have anything as good for Firefox though (I'm using Session Boss, but would like something better).