Originally Posted by jomama22
At a voltage of 1.3-1.4 could be handled by most reference designs. I am not taking credit away from the LNG, but its a fact that at these speeds/power levels, the power delivery delivery on 99% of reference based card (excluding the cheaped out xfx style) is just fine for our need.
Once we get into 1.5-1.7v then yes, a LNG style PCB helps.
It's not just the voltage. At ~1.4V ~1,400 MHz, the power draw is also very high. GK104 may be a very efficient chip, but at the speeds we are talking, we are looking at as much as 400W peak (on things like OCCT or Furmark) per card. I seriously doubt that any reference board could handle that for an extended period of time, hence my suggestion earlier that the VRMs could blow. There are 4+2 phases on the reference design, 4 for the core, which given the power draw we are talking about, could be a huge issue.
You are right though that ~1,400 MHz+ has been done before on stock:http://videocardz.com/32592/kingpin-reaches-1442-mhz-with-geforce-gtx-680-on-air
But for a 24-7 OC as many of the people in the 680 Lightning thread are doing? That will need an upgraded PCB. Again, it's not that MSI has a monopoly on this, it's that they have one of the best custom PCBs out on the market. Is it overkill and overengineered for just air? Indeed so. Is that a bad thing? So long as people are willing to pay for it and MSI makes a profit off of it, and it does help get a better OC (along with MSI's other tools, like Afterburner), it seems like a win-win to me.
Originally Posted by jomama22
And if Neilz would like to correct me, LNG chips are binned by their ability to hit x voltage at y clock. You do not bin with overclockablity or headroom at all. So the binning will only help you so much in terms of finding that golden chip. That is why most who want the best chip bin a bunch of reference cards:Cheaper and more available.
I have three lightning's, I am not dissing them. But have a look at the 7970 side of things and understand that the reference design has all the highest scores for non ln2. Why? Because the reference is enough to handle the current load and can change voltage. Getting a good overclocker is just part of the silicon lottery. No way around it.
Actually, I've even gone to the extent of creating a thread just to investigate.http://www.overclock.net/t/1405642/why-are-the-diamond-reference-7970s-overclocking-well-compared-to-the-other-brands-cards/0_100#post_20347371
You are right in that the custom PCB 7970s did not do well on air. However, there have been a few 7970s, such as the ones that won the silicon lottery that have been able to do 1,300 MHz+ on air, including a handful of reference cards, the Asus Matrix 7970 (although that card had a ton of other issues), and a handful of 7970 Lightnings (and the newer BEs). Air is always very heavily reliant on silicon lottery (and so is water). But that does not mean that having a good PCB does not help (as does MSI's TF series of coolers).
Originally Posted by neliz
Actually most Twin Frozr fans use Ball Bearing fans, especially on cards like Hawk/Lightning
Thanks for the tip. I did not know that.
Originally Posted by AJR1775
I'd rather an OC'd 780 than an OC'd Titan; I don't think the difference in performance would justify the difference in cost which is what, 70% to 80% higher?
The Titan's if there is a Titan Lightning might be more future-proof in a sense. Games today do not need 3gb+ of VRAM. But there are some games, like Skyrim with the texture mods, and with the expected proliferation of 4K displays in the coming years, 6gb of VRAM might be more valuable.
I mean the Titan's 6gb was intended for GPGPU uses, but that also may make it useful for other things, like if you plan on using 3x 2560x1600/1440 screens as well. And if 3x 2560 or a 4K screen is in the budget, then perhaps so is a Titan.Edited by CrazyElf - 7/10/13 at 6:48pm