Is memory clock linked to core voltage?

[AstroBenny]

Hi, I have a reference GTX 970  and I am planning to overclock in MSI Afterburner but I have a few questions.

1) I understand that as you increase the core clock it requires more core voltage to keep it stable but there is no memory voltage slider. Does this mean that you just push the memory clock as far as it will go without artifacts or crashing? Or does it inherently become more stable as the core voltage is increased?

Or is there actually a memory voltage slider which I can't find And what are the artifacts associated with an unstable memory clock.

 

2) I have posted this question before but the answers were rather...vague.

 I have a reference GTX 970 and am wondering what the difference voltage control modes are in my afterburner settings.I have the option between reference design, standard msi. and extended msi.

Which should I use, and what's the difference between them?

Cheers,

Ben

 

SPECS:

i5 4690K

GTX 970 Reference from OCUK

Corsair Vengeance 8GB 1886Mhz

Asus Maximus VII Hero

Corsair AX760i

WD Black 1TB

[PhiberOptik]

1)There is a memory slider, it is a special feature for some GPUs. Yes, just push it. No, core voltage is core voltage only.
2) Probably opens up additional options, I have MSI Afterburner and have never seen or used that to overclock my GPU.