The idea that it gets better with more dmg yes but I don’t know why everyone is ignoring that we already came to that conclusion and the base dmg also makes a diff and also the amount of INT as it gives a 4% dmg bonus on base, and on top of that glacier has a 3.5x multiplier to spell dmg/cold dmg, so for spells like that the “breakpoint” is much lower and that’s why I couldn’t make sense of what he was saying. I’m getting frustrated trying to have a discussion when people don’t read the thread and trying to understand people that didn’t read what I’ve added. EDIT : I read in a dev post that skill modifiers are multiplicative so it’s more complicated than the chart suggested. I was using a set of example numbers to draw the conclusion and i’m not going to even pretend to know the breakpoint and say it’s the same for any build when it’s not.
None of that actually makes a difference because it’s largely fixed if you’re just wondering whether a 9% pen affix on your amulet is better than an additional ~70% increased XXX damage affix.
If the 9% pen affix is more effective than the 70% increased damage affix then the fact that glacier has a large modifer doesn’t actually matter, it just makes the numerical difference (and by that I mean the actual damage) bigger, but the % difference between the two will stay the same. So if the pen affix gives you 10% higher damage than the increased damage affix, then it doesn’t matter if the numbers are 1,100 v 1,000 or 1,100,000 v 1,000,000, it’s still 10%.
does the chart I posted above not show how it’s not linear? (the results of the 9% pen)
I kind of drifted away from the topic when I came to the conclusion the devs were smart about when we started to see pen amulets drop in the game. It’s right about the time it will start to be more effective than spell dmg %
look at the pen.txt document I posted. it is a more accurate comparison between 3 diff character states, adding one more dmg modifier, vs adding 9% pen modifier. The rough dmg outputs I used for a reason, because they are around the numbers on a target dummy between lvl 50-90 glacier crits. (10-30k)
I’ll do some maths when I’ve finished work…
It’s already there…pen.txt (509 Bytes)
If you want to help me explain why this is wrong because I don’t think it is and I understand this. The first 3 examples are 3 diff dmg mod states, the next 3 are the same states +70% and the last 3 are the original 3 with 9% pen multiplied after. It’s pretty clear when 9% pen gets better than 70% spell dmg. The top row is assuming 1k base dmg (after skill modifiers and int) and the bottom row is assuming 2k base dmg. The devs have stated skill mods are multiplicative with gear mods, so that’s the only way to do it as far as I can tell. The assumption there isn’t multipliers before added “spell dmg/ele dmg” multiplier is false. One of the conclusions I also made is that I was underprioritizing int. I got more Int also as it adds to the skill dmg and saw a big damage bonus (and didn’t take off my 9% pen ammy).
The breakpoint is when the incremental benefit from one modifier is equal to the imcremental benefit from the other.
With your 70% inc damage & 9% pen affixes it’s when you have ~700% increased damage from other gear/passives/etc, then the 70% increased affix gives ~9% higher damage which is equal to the 9% higher damage you get from the 9% pen (assuming you have no other sources of pen).
As you can see from the above, when the amount of “base” increased damage gets above 700% the pen affix is more effective at increasing the damage you do.
Mmm…math. This is certainly a great little thread.
And I laughed at this…cuz I imagine it’s what actually happened. 
Okay even though I don’t think you guys were understanding what I was saying I was wrong assuming that the base multipliers changed the breakpoint and I estimated it to be slightly lower than it actually is (I thought around 5-600%) but I didn’t actually do that math I just inferred… Sorry i was really tired and going over a bunch of things I shoulda got some sleep (did now). Thanks bro. Do we not have an option to mark a comment as the solution? I would take your last comment as solution.
Entirely possible, and I would have done that earlier had I not been busy at work…
Been there, done that, got the t-shirt. 
Unfortunately, that functionality is only available for posts in the bug/tech support areas of the forum.
hey I thought of something, we missed crit multiplier. If I understand correctly cold pen gets calculated after crit multiplier which would make the breakpoint lower for crit builds. I checked for 580% with a 2.5 crit multiplier and 9% pen was already more dmg than 70% spell dmg
Well, that would be a separate conversation, since we didn’t look at crit & crit multi… Since crits are a separate layer of damage multiplier, they function like a 100% “more” modifier that you get if you get a crit, therefore it would only change the numbers rather than the result.
so a 250% crit just adds 250% spell dmg… that doesn’t make sense… it should multiply the result of the base and the dmg modifiers… which would change the result
No, it increases your crit multi from x2 to x2.25.
So if you had a hit for 1,000 & you crit, normally you’d do 2,000. But with 225% crit multi you’d do 2,250. If that 1,000 was with no other modifiers, then adding 25% inc damage would increase it to 1,250. Critting (with only a 200% crit multi) would then increase that to 2,500.
yea that’s what i mean,
base dmg 1000
spell dmg 650% 1000 x 7.5 = 7500 * 2.5 18750
spell dmg 720 % (70sp) 1000 x 8.2 = 8200 * 2.5 = 20500
spell dmg 650% (9 pen) 1000 x 7.5 = 7500 * 2.5 * 1.09 = 22437.5
(250% crit muttiplier)
more dmg from the pen under the breakpoint no?
No, because the 70% spell damage is a 10.7% increase over the 650%, with that much “base” spell damage the 70% spell damage affix would be more effective.
1000 * 7.5 * 2.5 = 18,750
1000 * 8.2 * 2.5 = 20,500
1000 * 7.5 * 1.09 * 2.5 = 20,437.5
You took the 20,500 (720% spell damage figure) & then added the 9% pen.
Adding an extra layer (the crit multi) into the calculation doesn’t change which gives more, it just makes both numbers bigger.
so you’re saying the dmg reduction and resistance calculations happen in the same formula as the dmg calculations? that’s strange… do you have the actual formulas the game uses?
No, I never mentioned those at all, I was just saying that your penetration calc was wrong because you multiplied 20,500 (the result of using 720%) by 1.09 instead of 18,750 (the result of using 650%).
My final paragraph was just meant to say that adding an additional term to the formula just makes the numbers bigger, it doesn’t change which is better (70% spell damage or 9% pen) given your starting parameter (the only one that matters is the 650% starting damage modifier).
no the result of adding 70% spellpower is the * 8.2 calculation. 7.5 is correct for 650% to add the base back in. 1000 with 650% added is 1000 + (1000 x 6.5) or just 1000 * 7.5… atleast I think.
720% spellpower is * 8.2 that’s the added 70% spell dmg.
(it’s added dmg otherwise having 0 spell dmg multiplier would result in zero dmg)