I've been working on overclocking my new Galaxy GTX 670 GC card following this guide: http://www.overclock.net/t/1265110/the-gtx-670-overcloc...
At the moment the highest GPU Clock Offset I've been able to get is a measly +30MHz for a max boost of 1167MHz. This seems really low based on what other people are getting with their 670's. I've been using Precision X and running the Heaven Benchmark which at anything higher than +30MHz crashes the NVIDIA drivers. Over the course of the benchmark my Power Target never seems to go above 77% and the temperatures haven't gone above 55C. Upon crashing however the Power Target seems to jump right up to 259% for a very short space of time for some reason. I've increased the voltage up to 1.175V and still no stability. Do I have a really bad card, have I done something wrong or are the drivers just playing up? My current drivers are 301.42.
Many of these cards are already working close to their power and sometimes their thermal limits for reference designed cards. Second it is likely the 30mhz overclock cap is preset in the driver to keep people from trying higher clocks that will likely lead to the degradation or sudden failure of their cards. The non reference models likely have a slightly different bios rom that allow for uncapped clocks much like what was seen on Fermi cards when it came to max voltage.
So far it appears that the max boost achieved with your card is 1280 MHz.
Which leaves you with these results, if you achieve the average results: 185 MHz. If your able to attain the 1280 MHz boost, 275 MHz gain.
My personal experience with the Galaxy Cards is that they tend to have very, very little overclocking headroom. They are cheap in price; deliver nice overclocks by default over a reference card. But they fail fairly quick when 'attaining' those really high overclocks.
With one of my GTX 580's altering the bio's helped me achieve a stable 975 MHz. A crash here and there; but stable for the most part. You may try that route if you wish to try and go significantly further.
But I'm going to ask an important question.
If the card can handle all your current games on the highest resolution and settings, if it does it may not be worth overclocking? Then when you start to hit performance issues, sell the card and buy a Evga or Asus. That way you can buy a newer card, plus that card will more then likely have better overclocking.
@Nforce4max Your also bringing up a valid point; even though his card is a better overclocked edition with nice gains. His thermal and power limits may already be hit. Which would obviously cause his current issue.
Based on that card and it's components I'd expect it to be able to achieve better overclocking. But I can't see why you shouldn't be able to achieve a 1200 MHz pretty easy. The boosted clock rate seems to have a solid reference hitting 1200 MHz easy.
1. Put regular clock rate to 1111 MHz
2. Overclock memory; try to attain the 6.46 GHz setting.
3. Max out your power ratio.
4. Try and achieve higher overclock settings again.