In the first post, we took a look at the memory usage between Firefox, IE9, Chrome, Safari — and the oddball, Outlook — on Windows 7 32-bit. However, I only had one tab open in each browser, so it wasn’t a very good test. I should also note: this time around, I’m using Windows 7 64-bit.

So for test #2, we’re opening eight tabs in each browser! And we’re getting rid of Safari and Outlook, because frankly — who cares? To be fair, I opened the same websites in each browser, which were:
- ESPN
- download.com
- eBay
- Lifehacker
- ign.com
- Wikipedia
So will Firefox remain the king of bloat, as we saw the first time around? Or will it be succeeded by a surly rival?
OK, you’re sick of drama. Without further ado, here is the memory usage of each browser, all of them running with eight tabs open for about 15 minutes:

The facts:
- Firefox used 197,812 KB or 263,412 KB (193 MB – 257 MB), depending if you count the plugin-container.exe that it seemed to spawn (when I killed Firefox, it went away).
- Internet Explorer 9 gobbled up 419,568 KB (410 MB) (!) when running with eight tabs open.
- Chrome consumed 300,572 KB (294 MB)
My, how the tables have turned! The trend reverses, and IE9 becomes the memory hog, and Firefox becomes the most “lean” by a long shot!

Contrast this to the chart from Part 1 (remember, this was 32-bit Windows):

So what does this mean? One of two things:
- Browser memory usage is wildly different on 32-bit Windows vs. 64-bit Windows
- Firefox is much more efficient when the amount of tabs increases
I’ll let you draw your own conclusions! If I do another test, I should definitely stick to either 32-bit or 64-bit, to remove that variable. What do you think? Has your experience of the browsers’ memory usage been consistent with my test, or different?

