What gear is better? High 800's with higher DPS or low 900's.

[Namesnotearl]

Hey guys, I play Frost Mage and DPS is low. People have fun killing me in PvP. What would be better for me in PvP or Dungeons higher gear or just a lower lvl gear with higher Critical Strike.

Thanks,

My name is not Earl

[Grevmak]

For PVP, the only thing that matters is itemlevel. Your stats are normalized in Battlegrounds and Arena and scale up a little by the amount of itemlevel you have, so wearing 900 will make you a bit stronger than wearing full 800 gear.

For PVE gear, there is no guaranteed way to say unless you sim it. Simming means downloading the addon Simulationcraft, typing /simc in chat, copying the text and pasting it over to a simming program or website and then you're told how much DPS you're supposed to do. Raidbots is great for this, it even shows you what stats are best for the next item you get, or can compare multiple itemsets.

If you just wanna know it quickly and not bother with simming: Just wear the highest itemlevel gear while minding basic stat weights listed on Icy-Veins. Copypasting from it:

The stat priority for a Frost Mage is:

Critical Strike (to 33.34% Shatter Cap);
Intellect;
Haste;
Versatility;
Mastery;
Critical Strike (after 33.34% Shatter Cap).

Again, these are just in case you want a rough estimate. If you really want to know, you gotta sim it.