Looking at the dev versions of the browsers, Firefox again took the crown, improving its memory usage still further. It's unbelievable. Even though the browser froze up for five seconds during our 15-tab test, it still achieved the best overall performance.

Chrome came in the heaviest this time yet again, with a combined memory utilization of 1,118 MB, followed closely by the alpha version of Opera 12. The screenshot below shows Chrome eating up memory in Process Explorer.

Now, I completely realize that these benchmarks do not necessarily represent your real-life usage. Everyone has their own browsing behavior, which may or may not exceed what I've tested here. Also, factors such as third-party plug-ins, operating systems, background tasks, and many of the other variables mentioned above may result a slightly different picture. But this test should at least give you a general picture of the browsers that tend to use the least and most memory.

If you never open more than five or ten content-heavy websites at the same time, you should never base your browser choice on memory consumption. It simply doesn't matter a lot if your browser consumes 50, 200, or 400 MB of RAM, even on lower-end machines. However, heavy tab multitaskers should steer clear of IE9, Chrome (in all its incarnations), and Opera (Beta). Just go with Firefox. With RAM levels quickly reaching 1 GB with just 15 tabs, you'll encounter sluggishness even on faster machines. Again, it simply doesn't matter if you've got 4, 8, or 16 GB of RAM -- a browser taking up 1 to 1.5 GB of RAM quickly reaches the limits of both the Windows' and its own memory management capabilities. Threads and handles run wild, paging starts kicking in, and overall reliability goes down with responsiveness.