This document provides some frequently asked questions about SiSoft Sandra. Please read the Help File as well!
Q: Why does it take so long to run the disk benchmark?
A: This occurs when you have a large amount of memory and a rather slow disk. In order to make accurate measurements, the disk and software cache must be swamped by using a test file at least twice as big, as big as possible. Since Windows uses a dynamically allocated disk cache which can be as large 80% of your total memory, Sandra must use a huge file which takes a long time to process. There is no other way since the cache cannot be turned off.
Q: Why does the rating vary between sequential runs?
A: Since the disk cache is dynamic, the size will increase after many disk operations. Since a disk benchmark does only disk operations it is likely that the cache will increase between runs up to the maximum size possible. Generally the bigger the cache the larger the index, therefore the index should increase slightly between runs. When the size of the cache is constant the index should not vary appreciably.
Q: Why is Sandra unable to detect the exact speed of 16X or higher CD-ROMs ?
A: The 16X or higher CD-ROMs achieve the rated speed only when the test data file is stored on the outer tracks. If the data file selected by the test happens to be located at inner tracks, the test result will be slower than what the vendors specified. Also due to various overheads you will never get the maximum data transfer from the drive.
Q: I have CD QuickCache and Sandra crashes when running the CD-ROM benchmark.
A: Try and update to a newer version of Sandra or the CD-ROM caching software.