GPU Overclock Voltage Question

[RayF]

Firstly, apologies if I'm posting this is in the wrong place and it should be in the "Overclocking section". This is my first venture into overclocking and first time posting on this site.

I'm trying to overclock my Zotac 980ti Amp Omega. Following several guides I have gradually stepped the core clock up by +120MHz and Memory Clock by +225MHZ without any increasing in voltages. At these settings it's rock solid.

If I try to go any higher on the core or memory the system becomes unstable. All the guides say that it at this stage that I should start to increase the voltages. I've used MSI Afterburner and bumped voltages, power limits and temp limits up but it doesn't make any difference. The system still becomes unstable even at Core Voltage +87mV, Power Limit 110% and Temp Limit 87 deg.

I've also noticed that when I stress test in Kombustor the GPU never goes above 68 degree, regardless of me maxing out the setting and letting it run for an hour.

Am I missing something/doing something wrong or have I just reached the limit of the card?

Ray

 

[Awahwah]

It's possible you have reached your cards limit. For example, my card does not like additional volts at all.

But, start with the core first then work on the memory.

 

[8 Pack]

You probably need lower temps for more mhz now rather than volts. This is how many Maxwell GPU are when overclocked. They respond to cooler temps first and then volts at cooler temps.

 

[Rroff]

As 8 Pack said nVidia cards often respond to cooler temps than voltage - with my 780 I get the same max clock (before random black screens in heaven benchmark) with the last 2 voltage steps regardless at normal temperature levels - stick the PC in a temperature controlled environment where I can pull the ambient down to <12C and it'll clock loads more and the extra volts are good for something.