Just a little comment regarding your article: you do not need to have both /3GB and /PAE in order to enable AWE. All you really need is the PAE switch for the OS to recognize the memory above 4GB.

Infact, the high IO was probably the result of paging to disk (I couldn't find in the article the type of IO you were referring to), which the /3GB may have solved alone. Indeed, the extra 1GB allocated to SQL as a result of this switch may have removed most of your IO problems (it usually does). That's because more memory (1GB) is available to store you data pages.

The AWE switch means that the extra memory is used to store data pages only (so the extended memory is useless for the cache). This means that the /3GB switch solved your procedure cache problems.

AWE (with PAE) can reduce your IO if after enabling 3GB you still experience paging. One counter to watch for is the PLE (Page Life Expectancy). If this counter drops below 300 (on average), more memory is needed - it indicates that pages stay on average less than 5 minutes in memory before being swapped out.

The point I am trying to make is that 3GB is a switch totally independent from PAE and AWE, and that it alone may have resolved all the symptoms described in your article. Adding PAE and AWE may have been necessary in your case on top of 3GB, which is usually dictated by the PLE counter.

Thanks