Asus 770 Direct CU II Core Voltage Locked?

Dyingpie1

Honorable
Mar 10, 2013
30
0
10,540
Hi Toms-hardware users,
I recently upgraded my GPU (a EVGA 650 ti to an Asus 770) and it's running great! Except for one thing. When I try to increase the core voltage while overclocking the 770 in Asus GPUTweak, when I click apply, the voltage goes back to the default voltage. I have tried restarting the PC, reseating the GPU. I also have gpu voltage checked in MSI Afterburner settings. Still nothing! I also have tried it through MSI Afterburner, but in there I can't even get access to the voltage slider. Does anyone have an idea how to fix this?

My specs are:

AMD FX 8350 (OC to 4.8 GHZ)
ASUS 770 Direct CU II
ASUS Sabertooth 990fx r2.0
16GB Crucial Ballistix 1600 MHz RAM
Corsair Gaming Series 800 Watt PSU
Corsair h100i
Samsung 840 120GB SSD
Seagate 2 TB HDD 7200 RPM

Please reply with any questions :).