The 2.2Volts means Crucial warranties your ram at that voltage.
Any DDR2, doesn't matter what speed, the stock voltage is still 1.8Volts.
Except for those DDR2's which is above PC2-6400 800MHz
These sticks are Value Series from Gskill and not using D9GMH.Might be Elpida or ProMos.I have seen them hitting 580MHz.
IMHO,The Crucial deal is alot better than this one.Maybe this deal for G.Skill fans out there?