I believe they are all voltage locked, you may be able to raise the power to 133 percent if you have all the pci-e connectors hooked up but you won't see any performance increase as voltage appears to be the limiting factor for overclocking.are you using all 4 8 pin or dedicated 12 pin? that's the only way. also in afterburner make sure you went in to settings and "unlock voltage control" and even though i have an asus card i had to change the dropdown box to "msi extended" to get the full unlock on my card, so you could experiment with those settings. also make sure you have latest release of afterburner??