How much voltage is too much

Im looking to vmodd my Asrock Dual sata2 for more voltage memory, as the max right now is about 2.7... I think the Vmodd brings it up to around 3.1-3.3... would this be safe?

That would depend on what memory you have, it would also be easier to supply that voltage using the ocz booster, provided your mobo is on the compatability list. Not all memory responds to higher voltage (Mushkin redline for example loves more voltage)

http://www.techpowerup.com/articles//overclocking/voltmods/130/3
if you haven't found it already

though twajet has a good point.. not all ram like high voltages. i see you have 2gb of ram in your sig.. if it's 2xs1gb, most likely you won't need more than 2.9v to get the most our of your ram.