I know this is alot to read but you need to check this out. I was totally blown away at how much money I wasted. Time to ReGem I thinks....

By: Swindley (EU-Frostwhisper)

Basics first:

First of all, each stat has a value on an item.

+1dmg costs 0.855 to increase on itembudget, while +1 spellcrit costs 1. So +dmg is cheaper to increase than +crit. (compare +8 critgems to +9 dmg etc)
School specific +dmg costs 0,7. (spellfire uses this formula as far as I know, even if it's 2 schools)

+1 spellhit is also worth +1 on itembudget/level.

You need 22.1 critrating for 1% more to crit and 12.6 +hit for 1% to hit.

Easier to calculate is +1% hit. +1% hit will give you +1% dmg, and is cheap and easy to increase. Aiming for +16% hit should be the goal for raid bosses. It will improve your dps the most for the smallest amount of itemcost.
edit: it's actually slightly better than 1%, and also since that missed spell could have crit, giving you 1/3 mana back, it also passively improves efficiency by a little bit.


Now here's the first interesting calc that alot of people are forgetting.
People assume 1% more crit will give them 1% more damage. This is wrong. That is assuming you already have 0% crit, which you probably don't.

Assuming you have 30%, which is OK, each +1% to crit will increase the damage on 70% of your spells by 1%.

For full fire that is 70% of 1.1% (with ignite) = 0,827%. Meaning 22.1 crit rating will increase your dps by 0,827%.

For arc/fire, these numbers change a bit, also assuming 30% crit already for easy calculating. For 22.1 crit rating
70% of 1.45 % (spellpower and ignite)
1.010%


This means, crit rating is a little bit more beneficial to arc/fire than full fire, which is no surprise.

But now let's look at full fire and +dmg. Seeing as +dmg gets benefit from all the Fire damage increasing talents (13%) then +1dmg is +1.13 dmg.
But people also often forget here that they do not have 0% crit, as the +dmg can also crit.
Assuming once again 30% crit rating, +1dmg
1.13 x 1.3 = 1.469

Let's assume you never get coe, only the +15% scorch dmg debuff.
Afaik the talents are also multiplicative, meaning +1.469 x 1.15 = 1.689

If you're spamming fireball, add another +5% to the effect +dmg gets
(Improved + Empowered fireball is total +105% of your +dmg, damn coefficiency nerf;)
(scorch gets +43% for half the cast, obviously a lot worse for DPS)

So each point of +1dmg is worth +1.689dmg while +1 critrating is really worth +0,827 crit rating, assuming 30% already crit rate.
(meaning you need ~26.5 crit rating for about 1% total dmg increase)


Meaning +dmg is TWICE as good for increasing your dps as crit rating is.
I repeat, TWICE the value. And it's cheaper to increase, as it costs less on itembudget than crit rating does.

Now for another calc, which will be fairly inaccurate. ~+26.5 crit rating will give you +1% more dps. (as full fire) Easy numbers.

How much will then ~+26.5 dmg give in dps increase? First off, with talents and current crit rating, +26.5 dmg converts into +44.75 dmg.
(I could even be cheesy and add another +10% to those +dmg numbers, as +dmg is cheaper on itembudget, but I won't, since this is to compare items.)

Now the calcs get a bit harder, as it's assuming so much about your current gear, and how much dps increase 1% is etc.

So on a 3 sec cast fireball: +26,5dmg x 1.689 --> 44,75 /3 = 14.91 dps increase.
While 26.5 crit rating will give you +1% more DPS. Meaning you'd have to do 1491+ dps for +1 crit to get better than +1dmg. It's possible, but would take a lot of +dmg for crit to get better.
I'm guessing 1000dps is realistic on a static boss fight with none or little movement. (from experience)
If your gear is lower, +dmg will get even bigger benefit.

+crit will be better than +dmg eventually on scaling, but at a ridiculously high amount of +dmg.


But as a closing note. Crit is also good for MOE and procs and similar, so shouldn't be ignored.
And also, stacking a single stat on an item is more expensive on the itembudget than stacking 2 different ones.

So an item with +50dmg and +20 crit will off course be better than just +60 dmg. (and also help MOE etc)


Edit: I did the same calculations for arc/fire, and I think the conclusion was that at about 1200dps, self buffed only, crit gets better than +dmg. 1200+dps can be hard to pull off through a whole bossfight, but if your +dmg is already stacked sky high, (I'd guess +1300 dmg or more) AND you have the lightning capacitor, then crit will increase your DPS more than +dmg will.

At 40% crit with scorch, which is high, will make the capacitor proc every 11.25 sec on average, adding ~900 dmg average with crits. = +80dps. Although scorching is a bit lower DPS than Fireballing would be, this trinket helps make up for the difference, and you'll be more mana effective as well.


Conclusion: +hit will actually give you highest DPS. increase on raid bosses, up to +16% with talents, while generally you should be stacking +dmg, while getting the odd crit on items when you can. Choosing the same amount of +crit on an item instead of +dmg is generally slightly gimping your DPS in total.


Runed Living Rubies in everything unless the socket bonus is really worth it.
Or the new +hit +dmg gems if you can find them, Veiled Noble Topaz.


Math geniouses, I call on you:

So lets convert those formulas to a real world example. Let's take a fire mage with 900 spelldamage, 100 hit rating, and 30% to crit with fire.

+50 spell damage would mean (B+c*(D+n))/(B+c*D)
(902.5+1.035*(900+50)) / (902.5+1.035*900)
1885.75 / 1834 = 1.0282 which is 2.82% more DPS.

+50 spell crit rating would translate to 2.26244 more crit chance (1.1*(C+n)+1) / (1.1*C+1)
(1.1*(0.3+0.0226244)+1) / (1.1*(0.3)+1)
1.35488684 / 1.33 = 1.0187 which is 1.87% more DPS.

+50 spell hit rating is 3.96825 more hit chance on top of the 7,93651 hit chance the mage already has (0.83+H+n)/(0.83+H)
(0,83 + 0,0793651 + 0,0396825)/(0,83+0,0793651)
0,9490476/0,9093651 = 1,0436 meaning a whopping 4,36% more increase in DPS!

interesting indeed, i htink it can work for hunters too, not in the same way but im pretty sure increasing hit rating is the best way to beging to max dps

Very interesting Uly, thanks.
Ive known for a long time and its been said over and over that on raid bosses especially (considered to be lvl 73), +hit rating is the most important factor in means of overall damage, until you are high enough to never miss.
Although as a hunter, ive recently been experimenting with a bit less than my cap, which is 137 or for non survival hunters, and I feel that I am ok around 120, as I dont see any misses yet from the logs I have been checking, and since for me the +hit costs in +dmg, which my pet damage scales with, being a BM hunter this gimps me.

I will add that this totall screwed me up seeing as I am mostly Crit + Damage gems. I am going to have to get with Lilley tonight if she is on and start changing out some if not all of my Gems....

Uly

Ehn. Doesn't help me straight away as majority of my crit is from gear atm rather than gems, but it does make my mind up about not worrying about losing crit and switching one of my trinkets to a damage one instead. The author seems to be suggesting that 30% crit is an ok figure to aim at and then switching to damage though I may be reading wrong.

I can't say though I've noticed a huge increase in my dps since I increased my hit rating, but maybe it just isn't enough yet to make that crucial difference (still 25 off the cap if I remember rightly atm).

Imba topic.

i heared to stack hit rating at start.. so i did.
i never saw any maths with this

i always toughed +dmg would be more beneficial then +crit.
and this proves it.

this does meen i need to redo some gems/etc also

maby my dps will go up more.

EQ.

I'm assuming the same mechanics will generally apply to a destro lock, which is after all, a glorified mage.

Which is nice because all my gems are +dmg or +hit

/cheer for not having to spend more g