Paolo
I would guess at 133 because of the position of the clamp slots on the sides of the module. 100 clamps were usually lower down the module.
as cdogg said to me earlier:
You are correct. The memory bus will run at 100MHz and PC133 is backwards compatible.
Typical problems with PC133 on older PC100 motherboards deals with density. Newer PC133 chips (128MB and higher) are usually more dense and/or single-sided. If you have problems seeing the entire amount, then that's probably why.
If you have other problems like not being able to see it at all, then that's a different issue dealing with compatibility. Generic RAM isn't usually tested to run at slower speeds thus affecting stability.
So you may as well just buy some 133.
Good Luck! Please let us know what you think of posts, feedback is always appreciated as this will help to further our knowledge as well.
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