Original Link: http://www.anandtech.com/show/2691



While we've been holding our breath for a die-shrunk GT200, in the first announcement of something really new since the introduction of GT200, NVIDIA is promising a single card multi-GPU solution based on a GPU that falls between a GTX 260 core 216 and a GTX 280 in terms of performance. The fact that the first thing we hear after GT200 is another ultra high end launch is interesting. If the end result is pushing the GeForce GTX 260 under $200, and the GTX 280 under $300, then we can definitely get behind that: it would be sort of a midrange re-introduction by pushing current GT200 parts down in price. While we'd love to see parts from NVIDIA designed for budget minded consumers based on their new technology, the current direction does appear to be a viable alternative.


Image courtesy NVIDIA

To be fair, we don't know yet what is going to happen to GTX 260 and GTX 280 pricing. It is possible today, through combinations of instant and mail-in rebates, to find the GTX 260 for $200 and the GTX 280 for $300, but these are the exception rather than the rule. If pre-rebate pricing could fall to these levels and below, much of NVIDIA's lack in providing affordable pricing for their excellent technology will be fixed. Of course, this seems like a tough pill to swallow for NVIDIA, as the GT200 die is huge. Pricing these parts so low has to be really eating into their margins.


Image courtesy NVIDIA

And yes, this is a complete divergence from a hard launch. This announcement is antecedent to retail availability by exactly 3 weeks. Hardware will not be available until January 8th. While we are happy to talk about product whenever we are allowed, it is still our opinion that hard launches are better for everyone. Talking about something before it launches can (and has in the past with both ATI and NVIDIA) lead to changes before launch that reduce performance or completely eliminate products. Especially around holidays. This is the most tempting and worst time to announce a product without availability.

But be that as it may, we have the information and there's no reason to deny it to our avid readers just because we wish NVIDIA were acting more responsibly.



A Quick Look Under The Hood

Our first concern, upon hearing about this hardware, was whether or not they could fit two of GTX 260 GPUs on a single card without melting PSUs. With only a 6 pin + 8 pin PCIe power configuration, this doesn't seem like quite enough to push the hardware. But then we learned something interesting: the GeForce GTX 295 is the first 55nm part from NVIDIA. Of course, the logical conclusion is that single GPU 55nm hardware might not be far behind, but that's not what we're here to talk about today.


Image courtesy NVIDIA

55nm is only a half node process, so we won't see huge changes in die-size (we don't have one yet, so we can't measure it), but the part should get a little smaller and cheaper to build. As well as a little easier to cool and lower power at the same performance levels (or NVIDIA could choose to push performance a little higher).


Image courtesy NVIDIA

As we briefly mentioned, the GPUs strapped on to this beast aren't your stock GTX 260 or GTX 280 parts. These chips are something like a GTX 280 with one memory channel disabled running at GTX 260 clock speeds. I suppose you could also look at them as GTX 260 ICs with all 10 TPCs enabled. Either way, you end up with something that has higher shader performance than a GTX 260 and lower memory bandwidth and fillrate (remember that ROPs are tied to memory channels, so this new part only has 28 rops instead of 32) than a GTX 280. This is a hybrid part.


Image courtesy NVIDIA

Our first thought was binning (or what AMD calls harvesting), but being that this is also a move to 55nm we have to rethink that. It isn't clear whether this chip will make it's way onto a single GPU board. But if it did, it would likely be capable of higher clock speeds due to the die shrink and would fall between the GTX 260 core 216 and GTX 280 in performance. Of course, this part may not end up on single GPU boards. We'll just have to wait and see.

What is clear, is that this is a solution gunning for the top. It is capable of quad SLI and sports not only two dual-link DVI outputs, but an HDMI out as well. It isn't clear whether all boards built will include the HDMI port the reference board includes, but more flexibility is always a good thing.


Image courtesy NVIDIA



Preliminary Thoughts

With a board power of 289W, this thing isn't going to be cheap to run. Plugging two in a system is going to push the envelope, but 3-way GTX 280 will still consume more power. It is likely that NVIDIA made the changes to memory bandwidth in order to save on a couple hundred megs of RAM that would draw too much more power. Making such a move is definitely sensible, but it is at the highest end (2560x1600 with tons of blur (I mean AA, sorry)) where tons of RAM are needed to push performance.

Of course, with two cards (especially if a game is capable of alternate frame rendering (AFR)), memory limited performance issues will be mitigated quite a bit, and opening up the shader power of two GTX 280 cards in a single slot is big for games that use a lot of compute. The way future games tackle the balance of compute and memory has yet to be seen, but NVIDIA has been saying for years that the future continues to be increasing the compute ratio.

We like hard launches. This isn't one. While that's disappointing, we do really want to get our hands on this hardware. The GTX 295 definitely looks like it will best the Radeon HD 4870 X2 in terms of raw power. Beyond that, it is clear that AMD hasn't taken driver development seriously enough and CrossFire just isn't as robust as SLI. Relying on a CrossFire based solution for their highest end part means it is necessary to provide reliable performance and stability across all games, new and old, and on all platforms. Making user defined profiles that allow the forcing of different CrossFire modes on certain games would go a long way to helping, but the real relief will come when AMD decides to fix their broken driver development model.

As it stands, SLI is a better solution than CrossFire and the GPUs on the GTX 295 will really put the screws to RV770. We will very likely see NVIDIA take back the crown in terms single card performance.

That said, how sad is it that NVIDIA had to go and push this press info out there 3 weeks before availability just to try and slow AMD's momentum during the holiday season.

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