Hello,
I received my very own EVGA GTX780 ACX SC edition last weekend. I've been playing around with Precision X a bit.
 
I got some okay results using the following offsets: +115 CPU, +275 Mem and setting Overvoltage to +38mV. 'Okay' because I still sometimes get a crash in Fire Strike (let's say 3 out of 10 times it crashes). CPU MHz go up to 1228. I'm planning to lower the CPU and Mem offset by increments of -5 and -10 for each run when I get home to see when it gets stable.
 
Questions:
I'm assuming that setting mV via Overvoltage to +38mV makes the card more stable in these offset regions. Am I assuming this correctly? If not, should I just lower it, or even put it on default (0)?
 
Are there any ACX SC users that want to share their offsets? I'm curious how well other cards perform.
 
Since I won't be going higher than 1228MHz since it will just get more unstable, I'm hoping to atleast reach ~1200MHz stable. Would this be a safe value to use permanently, assuming the temp is nicely inbetween 60-70c during full load?

loveha

It would make it more stable, but you also need to raise the Power Target. Most people just max that out. No over clock is technically safe. Just as long as you keep the temps down and don't do anything out of the ordinary like flash your GPU BIOS to something that alters the cards power performance in anyway you are still covered under EVGA's warranty which covers overclocking and it blowing up. So I would max the Voltage and the power target and try again.

Thanks for your reply. I cranked up my Power Target as well to 106%. Would 38mV be a good value for 106%? I'm not planning on drastic stuff like flashing... and like I said I won't likely go higher than 1228MHz since that's not 100% stable anyway.