[Guide] How to Soul Gems - Rubies
We all know that early on, raw attack is much better than anything else on gems. With high CR however, the gap gets closer and closer. But at which point do other gems become better, if at all?
Here's how you calc it. Take one ruby off, aka the ruby you're considering replacing with a different one.
Check your attack power, bonus damage and crit damage. Add 100 to the bonus damage, leave the other two stats untouched. Write down the 3 values.
Check the attack power, bonus damage and crit damage of the gems you intend using. If you don't own the gems yet, you can check their stats under "gemcraft" at the gem NPC. Write down the 3 values.
By the way, this is assuming your crit is capped, and your crit is capped. If it's not capped, go cap your crit. Slackers. Where were we? Oh yeah, gems, and stuff.
Divide the value you see on each gem for the respective value of your stat. aka
value of bonus damage ruby / (your bonus damage + 100 )
value of crit damage ruby / your crit damage
value of attack ruby / your attack
Check which number of the 3 is highest. That's the gem you want to use.
Exampuru, taking my WG's stats and VI gems.
Attack 39767 - Bonus damage 128,81% - Crit damage 350,61%
LV6 attack ruby 840 - LV6 bonus damage ruby 3,85% - LV6 crit damage ruby 6,65%
840/39767 = 0,021
3,85 / 228,81 (remember to add the 100) = 0,016
6,65/350 = 0,019
Conclusion: attack gems still better.
Attack gems scale better with leveling than crit/bonus damage gems. So check again if you're upgrading gems, for example from V to VI.
Attack will probably always be better at this stage of the game, only way of changing this would be the introduction of new BiS items that increase attack by a lot while leaving the other two stats relatively untouched.
Bonus damage on gems seems to always be a poor choice with the equipment we've got available right now.
Crit damage might have a cap of 400%, meaning stacking too much of it with gems could be a poor choice as well.
For more accurate results, check your stats outside town. Also, take into consideration frequent buffs such as vamp's Blood Drive, Kholdor Hat's passive and so on that might tip the scales. Your ultimate goal is to do more damage, not to have a bigger e-wang when sitting in town. Unless you're one of those people that put damage charms on their accessories for more CR, then do whatever the heck you want. You know who you are you freaks.
Hope this is of use.