Frost DK

http://elitistjerks.com/f72/t83319-frost_dps_3_3_3_will_day_long_remembered/#Stats

Stats

In order of importance:
If you are looking for stat weightings I suggest you use one of the many sims (I prefer simcraft) as the values will vary greatly depending on your current grear.

Hit
32.8 rating gives you 1% hit, therefore you will require 263 hit rating (164 with Nerves of Cold Steel) or 8%, to be hit capped on special attacks. This means, contrary to what some might think DW builds actually require less hit to cap their special attacks than our two handed brothers. Special attacks include: Blood Strike, Plague Strike, Frost strike, Obliterate. (and others that we don't care about as DW)

Spell hit cap is 17% against level 83 (boss level opponents. The talent Virulence provides 3% hit for spells, the Druid talent Improved Faerie fire, or the Shadow priest talent Misery will further reduce this requirement by 3% (Hit debuffs do not stack.) The final result brings the requirement via gear down to 11%, at which point no spell will miss. Spells include Howling blast, Icy touch and Death coil.

White hits have a hit cap of 27%. The talent Nerves of cold steel reduces this by 3%. At this point, no white hits (or any attack for that matter) will miss. This cap is not reasonable to reach for any DK, and should not be attempted. However, keep in mind that gaining hit over the spell hit cap still has a dps value as it will allow more white damage, more blood caked blade procs, and more Killing machine procs.

Expertise
8.2 rating gives 1 expertise; you need 214 expertise rating (26 expertise, 6.5%) to reach the cap, 5 of which is given to you freely from Tundra Stalker, bringing the required amount to attain from gear down to 21 expertise (172.2 rating). If you are a human using a sword/mace you need 18 expertise (147 rating), and if you are a dwarf using a mace or an orc using an axe you need 16 expertise (131.2 rating) to reach the cap due to racials. While not as important as the hit cap, capping expertise is still important as it will affect the majority of your damage.

Strength
This will be your biggest DPS gain after you reach the hit/exp caps. Since DKs have many different multipliers for strength, it works out that 1 strength ends up being woth about 2.7 AP. As all our abilities are affected by strength, this is easily the best stat for a hit/exp-capped Death Knight to stack.

Crit
You need 45.9 crit rating to gain 1% crit at 80. Since Frost DKs have very large crit multipliers, crit is more valuable for us than some other melee classes. While it's value will be diminished because of the disappearance of 4pT9, it is still one of the most valuable stats you can acquire.

Armor Penetration
13.8 rating is needed to get 1% armor penetration. Surprisingly, this not as bad a stat for Frost DKs as one might initially think, especially for single-target fights due to the heavy reliance on Obliterate and white hits. Spell damage from diseases and Frost Strike still make it undesirable to stack heavily though.

Haste
You need 25.21 baseline haste rating to gain 1% haste at 80. As a DW class with many proc based abilities, haste is more valuable for us than some other melee classes, but still not worth more than crit, strength or ArPen.

Attack Power
As mentioned before, all DK abilities scale off of AP. However, most stats that you will find end up being more valuable than raw AP, so it's not worth seeking it out .Note that despite AP having a 2:1 item stat budget, it is still far weaker than STR as we have no talents that boost it's effect. When comparing or considering pieces with AP vs plate, you need to look at the item stats/level as a whole.

Agility
We need 62.08 agility to gain 1% melee crit. Crit is significantly better, as Agi doesn't affect our spell crit and converts to crit at a much slower rate. However, it is still a decent stat for DKs.

Armor
DK with Bladed Armor get 0.027 AP per armor point. Most specs won't have BA, so they will not need to worry about this, but for those with BA, it makes plate gear just slightly more attractive than leather/mail.

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