Some have the stacking penalty notes but some don't and a CPM said all mods do even range amplifiers or dampener even though they don't have a stacking penalty note.

A good rule of thumb: If it modifies a value by a %, say 5% more damage, then it has stacking penalties. If it modifies it by a fixed number, say 22 more shield hitpoints, then they don't have stacking penalties.

Not the point, i know theres a stacking penalty for some modules that stack but what about modules that don't have the stacking penalty note.

That's just what I said, modules that increase or decrease something based on a percent will probably stack even if there is no note, so just assume they do and if they don't you'll be pleasantly surprised. On the other hand modules that give a fixed bonus almost never stack, at least I haven't found any that do, and they are easy to test if they do stack or not: just add the second one on and see if it gives you the full benefit.

I get tired of saying this:

The stacking penalty is property of an attribute, not a module.

From the current version of DFT, the following (among Dropsuit modules) have no stacking penalty:
- Effects on Armor and Shield attributes (both % based and fixed amount)
- Fixed value increases for PG
- Armor Repair Rate

Those are obvious, i'm saying does range, dampener and precision mod get stacking penalty?

Some have the stacking penalty notes but some don't and a CPM said all mods do even range amplifiers or dampener even though they don't have a stacking penalty note.