Thanks a lot guys.
I'm running Linux Mint Olivia on a Samsung laptop with NVIDIA. Just last night read up on the forum on this tutorial.
I'm now getting this when I run optirun glxgears (can't believe these figures are really true!!)
4712 frames in 5.0 seconds = 942.312 FPS
4881 frames in 5.0 seconds = 976.118 FPS
4865 frames in 5.0 seconds = 972.849 FPS
Mainly, my battery life has gone up from two and half hours to about 3:15 or so. I get close to 5:30 hours however, when I boot into Windows 8 on the same laptop.
I still am not getting good graphics on my Google Earth , get many pixellations and don't know why. I'm still looking around for answers.
Edited :- My battery meter often reads 3:45 to 4 hours plus standby time, depending on what I am doing. Thanks to Bumblebee!!