Another way to start or stop SuperFetch is to use the registry editor, Regedit. Navigate to HKEY_LOCAL_MACHINE/SYSTEM/CurrentControlSet/Control/Session Manager/MemoryManagement/PrefetchParameters
To switch off Superfetch, enter 0 into the Value data text box. Alternatively, you could also enter 1 to enable the prefetching when a program launches. Or you could enter 2 to activate boot prefetching in Windows. A value of 3 = 1 and 2, so 3 activates prefetch for program launch and prefetch for Windows boot. Remember to click the OK button.