So, in this first part, I will explain all the calculations that I'm doing, and I'll give you precise value of sockets in the second and third parts. First, let's explain something, you probably have a favorite secondary stat (usually mastery), that is better than others, but to what point is it better ? For example, assuming you have 0% haste and 0% critical, then, a +200 haste gem will give you 1.754% haste, when a +200 critical gem will only give you 1.600% critical, so you might think haste is a better choice. But to which point is it better ? If you have already 20% haste (and still 0% critical), a new gem will increase your haste by 1.754% but this now only increase your dps by (120+1.754)/120 = 1.462%, so it's now better to take a +200 critical gem that still increase your dps by 1.600%, right ? In fact, staking a stat is (almost) never good, because for example, having 20% haste, 20% critical, will increase your dps by 1.2*1.2 = 1.44, ie 44%, while having only haste or only critical will only increase your dps by 40%. That's why I recommend you (you can compute and check for yourself if it's better or not) to stack your main stat only to a certain point, then focus another one (for ex : mastery ring, then haste ring, then critical sockets, so no stat is too much stacked) Also, it's good to know that it's not good either to stack primary stat (intellect, strength and agility), unless that's the only possible way. Now, I can explain some of the computations that I've done so far on my characters (they are all geared with average 860-870 gears) : On my Balance Druid, a critical gem gives 1.600%, haste gives 1.754%, versa gives 1.351% and mastery gives 3.600%. Since he already has 51.50% critical, 25.25% haste, 30.31% versa, 197.71% mastery, and 23.911 intellect, a +200 gem in either primary or secondary stat will increase his dps by : 1.056% for critical, 1.400% for haste, 1.037% for versa, 1.821% for mastery, and 0.836% for intellect. Mastery doesn't boost every spell, so I think it's safe to say that 1.821% on only some specific spells is worth ~1.400% (like the haste gem). Conclusion : The best gem increase his dps by 1.400%,that means it's (1.400/0.836) = 1.675 times more effective than intellect !!! (yes, intellect sucks). Doing this for Affliction Warlock, Frost Dk and Elemental Shaman, I can see that best gem gives : for Warlock : ~1.400% dps, that's 1.561 times more effective than intellect for DK : 1.396% dps, that's 1.269 times more effective than strength for Shamy : 1.425% dps, that's 1.483 times more effective than intellect Conclusion : the best stat you have is, in average, 1.5 times better than your primary stat, so it means that if for example haste in your current (depends on what you already stacked) best stat, 100 haste will be worth 150 intellect (or strength, or agility) ! That's crazy, no ? --- Double Post Merged, Oct 15, 2017, Original Post Date: Oct 15, 2017 --- Now in this part, I will enter more in details about how much a gem is worth in terms of Ilvl. The tool we'll use is what we computed in part 1 : the ratio of how much your best secondary stat is worth in term of primary stat (so 1.5). Furthermore, we can also compute a ration between a randomly taken stat (because 200 of your best stat is probably better than +80 haste +120 critical that you'll get by increasing an item ilvl) and your primary stat, this coefficient is, on my own example, approximately 1.25. Keep in mind (it's extremly important), that these ratio are class / spec dependent. As we've seen, the 1.561 of my Warlock and the 1.269 of my Dk are really not the same coefficients !! So you'll kinda have to adapt the following arguments for your own character, even tho you can simply think about it this way : If you have high primary stat (so typicaly using 840+mace, or using 810/910 relics on intellect characters, or leggendary trinket), intellect is stacked, and is becoming less and less usefull, so gems are even more important. Also, if one secondary stat is really good, gems matter more too. Now, I've made computation (see part 3), and here is how we'll work this out. I'll do three typical item level (840, 860 and 880), and for every item for every ilvl, I'll tell you how much a socket is worth. Here is how I proceed (I show you in an example) : Cyno (840) gives 930 intellect, and 989 random secondary stats (the randomness is important, because it would be better if the 989 stats where the one you need, so 989 random is less than 989 of your best stat). Cyno (860) gives 1121 intellect, and 1067 random secondary stats, so in 20 ilvl you've won : 191 intellect, and 78 random secondary stats (worth 78*1.25 = 98 intellect). Conclusion : 20 ilvl gives worth 191+98 = 289 intellect, while a gem, gives you 200 of your best stat, so approximately 200*1.5 = 30 intellect. Then, we can see that a socket on a 840 Cyno gives approximately 21 ilvl (in term of dps, we forget stamina here). 21 might seem totally crazy high, but it's mathemiticaly the increase it's worth in term of dps. --- Double Post Merged, Oct 15, 2017 --- Now, I've shown you an example about how much a socket is worth on Cyno 840 shoulders. I'll do all the computations for other items now (knowing that I won't consider rings and necklace as "random stat", because we obviously choose the one we need for those items, something that is not the case for other items). I consider in the following that you're equipped with approximately everything in 860 ilvl (because I compare to myself), and now you add one last item. Then depending on this item's ilvl : For 840 items, a socket is worth : Rings / Necklace : 15 ilvl Wrists / Cloak : 27 ilvl Shoulders / Gloves / Belt / Boots : 21 ilvl Helmet / Chest / Legs : 16 ilvl For 860 items, a socket is worth : Rings / Necklace : 14 ilvl Wrists / Cloak : 24 ilvl Shoulders / Gloves / Belt / Boots : 18 ilvl Helmet / Chest / Legs : 14 ilvl For 880 items, a socket is worth : Rings / Necklace : 12 ilvl Wrists / Cloak : 21 ilvl Shoulders / Gloves / Belt / Boots : 16 ilvl Helmet / Chest / Legs : 12 ilvl These results are kinda strange because no one would expect a gem to be worth that much, but all of that is true Again, this is VERY important to acknowledge that these numbers change from a character to another. On my DK, all the number above would be overrated (by maybe 20%) and on my Warlock, they would be underrated (by maybe 20% also). Also, the 1.25 coefficient obviously depends on if your item is giving you your best stats or not. Remember what I told earlier (in second part) so you can adapt these results for yourself : "If you have high primary stat (so typicaly using 840+mace, or using 810/910 relics on intellect characters), intellect is stacked, and is becoming less and less usefull, so gems are even more important. Also, if one secondary stat is really good, gems matter more." Also, these results don't take in account defensive characteristic : Stamina is worth 0 here (so realistic for dps, not realistic in general), and in Versatility I counted the "reduce damage by..." part as useless (realistic for dps too, not in general). I hope you'll find this usefull, that might seem a little tricky to understand, but you can just focus on the table above, and on adapting it for yourself.