annoying hard disk activity noise

[sjivan]

I usually just turn off my monitor at night but for some reason, the HD constantly makes spinning noise even then the computer hasn't been used for hours ( i don't run time machine ). Is there any way to tell what process is causing this stupid HD activity? My previous Dell machine was soooo much more quiet than this POS. I prefer not having to explicitly put the machine the sleep every time.

[product26]

first of all, what machine do you have?

second. look under apple menu>system preferences> energy saver
and see what your sleep config is.

[aibo]

Probably spotlight indexing.

[sjivan]

I have a 2009 Mac Pro 2.66 / 8 core.

Settings attached.

[sjivan]

Probably spotlight indexing.

Is disabling it safe?

[Tesselator]

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