Investigating Intel's Turbo Memory: Does it really work?

Final Words

When Intel launched its fifth revision to Centrino, we were left mostly disappointed.  It was the most lackluster Centrino launch we had seen since the brand's inception and it almost seemed like a platform that was released for the sake of coming out with something new every year.  The sole feature we had high hopes for was Intel's Turbo Memory, but we were left sorely disappointed when we couldn't even find a use for it.

Some OEMs have publicly lashed out at Turbo Memory, stating that it basically does nothing for the user experience, which for the most part echos our findings internally.  The most recent data we've put together shows that Turbo Memory can have a positive impact on battery life, however the tests that show the impact aren't as easy to come by.  And honestly, savings of 8 minutes when watching a movie aren't impressive enough given the additional cost of adding Turbo Memory to a notebook (expected to be at least $100 USD). 

The best results we have seen however show promise for Turbo Memory; greater than 10% increases in battery life, resulting in an extra 20 minutes of active use time are nothing to scoff at.  The problem is how often and likely these scenarios are to occur vs. SYSMark-esque situations where Turbo Memory does nothing for battery life. 

Based on our usage, we'd expect to conservatively see 5 - 10% increases in battery life on average for normal usage, including simply watching a movie.  The improvement is there, but it's not as dramatic as we'd like to see.  Today's investigation sheds a little more light on what Intel's Turbo Memory can do, and clearly it has potential. 

There are two vectors Intel can scale along in order to improve the effectiveness of Turbo Memory: size and software.  The size vector is simple; the larger the ReadyDrive cache, the more data you can put it in, and thus the longer the hard disk can remain asleep.  The software vector may end up falling into Microsoft's lap more than Intel's, but the idea is this: the more aggressive the prefetchers are that populate Turbo Memory, the more likely you are to gain power and performance benefits. 

Sony has publicly stated that at the last minute, Microsoft removed code from Windows Vista that would more intelligently populate the ReadyDrive partition in an attempt to get Vista out on time.  Whether or not this is true is up for debate, but clearly there's room for improvement here.  Vista's SuperFetch works quite intelligently and it would seem that tighter coupling (assuming some already exists today) between SuperFetch and Turbo Memory could yield even more positive benefits. 

On the desktop the benefits are even less clear, since shaving a couple of watts off of the total system power isn't as big of a deal.  There are potential performance implications, but we suspect that the ReadyDrive flash size needs to be increased dramatically and be far more aggressive in prefetching to generate real interest. 

We leave today with a more hopeful outlook for Intel's Turbo Memory, but it's clear that the technology is in its infancy.  We stand by our original conclusion with regards to the Santa Rosa platform, as it isn't one that you absolutely need to upgrade to, it is barely evolutionary by Intel's own standards.  Turbo Memory could be nice to have, but your mileage may vary.  We'd suggest waiting for the second revision of the technology, hopefully by the next Centrino launch in 2008 we will see larger flash sizes and more software optimizations for the technology.