Frank “CTitanic” Garcia has been on the trail of background processes and services in Microsoft’s Vista OS that slow down or degrade performance in mobile devices like a dog on the hunt. He’s recently posted an article on his discoveries about Superfetch, which is designed, among other things,  to load the programs you use most frequently into memory so that they will load more quickly when called.

What Frank is positing is that this only works as designed depending on the hardware you're running (amount of memory and hard drive speed.)

What I have found, if you have 2 Gb or more of RAM and a fast HDD (7200 RPM or more or a SDD), Superfetch will do what Microsoft says it should do. If you have 1 Gb of RAM or less and a HDD running at 4200 RPM you should be thinking about turning off this feature because you HDD activity wont let you work.

It certainly appears slower spinning HD’s could be the villain in all of the “disk-thrashing” that so many are experiencing. Which is frustrating given the responses from OEM’s when many bloggers and pundits questioned the inclusion of the slower spinning drives on these mobile devices. We heard often that given how Vista operated behind the scenes that a 4200rpm or 5400rpm drive worked better with the mobile processors, than faster options. My suspicion on this is that no one really checked all of this out over time. In my personal experience, things seem to do better in the early going with a new system or new install. It is only after time that you begin to see the disk thrashing that can bring things to a halt. This makes sense when you consider that Superfetch is learning how you operate the machine.