Vatos locos:
You talk about GDDR3 me and Riska talk about GDDR4 and 2.3v is ALOT (!!!) for GDDR4 .....

I wouldn't go any higher then 2.1v for everyday use under good cooling ....

I didn't do any thing special to hit 1400Mhz and that was on 1.95v, take of the mem HS and take a pic of one mem modul or just write down what is writen on it, also interesting to know what brand your card is Riska, mine is
Sapphire

Edit: i have done the OCP mod on both of my cards and they still lives
The resistors to replace is very small, i used size 0805 and they was a little to big so 0605 should fit just fine