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The guides are floating around the web stating that Windows 7 automatically disables SuperFetch if it finds that disk is SSD.

However, my SSD is only 60GB, and I still have 3 TB of storage on HDDs containing video games, utilities and assorted stuff. I believe these files are good candidates to be prefetched by windows, however SuperFetch service was set to Manual mode and I did not catch it running yet. I can't remember touching this service, so it must be system that did it.

Is it wise to disable SuperFetch service in this case?

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Microsoft stated that they only found Superfetch (on systems with an SSD) makes a difference if the SSD's read access latency is slow.

Superfetch was designed to place often used data into memory. When a program goes to launch and load up files it needs, much of the time is spent reading files from disk. Now if the disk is the bottleneck, superfetch helps in this case, since the files are already in memory. If disk access isn't the bottleneck as is the case with current generation SSDs, then you will see little benefit from already loading the files into memory.

The only sure path is to benchmark. Since you have programs on the non SSD harddrive, I'd say turn on Superfetch.

Some say turning it off to save on the SSD's write endurance. This may be the case for older SSDs. Not likely the case if your SSD is one of the newer ones (released in the past year).

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I also feel that SuperFetch should be enabled. However, it was disabled by system itself and I think that my use case is not particularly obscure, so it is likely it was taken into account by Microsoft. Thus, I think there may be some valid reasons for disabling this service. – boomie Dec 20 '11 at 11:16
Like I said, the only sure path is to benchmark. – surfasb Dec 20 '11 at 11:44

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