Enter the GeForce 6600 series
NV43 will make its way to store shelves in two flavors: the GeForce 6600 and the GeForce 6600 GT. The GT will be clocked at 500MHz for both the graphics core and memory, while the vanilla 6600 will carry a core clock speed of 300MHz. Board vendors will be free to set their own clock speeds for the 6600's memory, so we could see some variety there. As far as memory types are concerned, the GeForce 6600 GT's higher clock speeds demand GDDR3, while the vanilla 6600 can get by with plain old DDR memory.
Priced at $149 and $199, respectively, the PCI-Express GeForce 6600 and 6600 GT will face off against ATI's Radeon X600 Pro and X600 XT, and possibly even the X300 XT. Here's how they all compare when it comes to fill rates and memory bandwidth:
|Core clock (MHz)||Pixel pipelines||Peak fill rate (Mpixels/s)||Texture units per pixel pipeline||Peak fill rate (Mtexels/s)||Memory clock (MHz)||Memory bus width (bits)||Peak memory bandwidth (GB/s)|
|Radeon X600 Pro||400||4||1600||1||1600||300||128||9.6|
|Radeon X600 XT||500||4||2000||1||2000||370||128||11.8|
|GeForce 6600 GT||500||8||4000||1||4000||500||128||16.0|
Theoretical fill rate and memory bandwidth peaks aren't the be all and end all of graphics performance, but they can hint at a card's potential. As far as potential goes, the GeForce 6600s have plenty. Although their core clock speeds are unremarkableor even low in the case of the GeForce 6600when compared with ATI's Radeon X600 line, NV43's eight pixel pipelines give the 6600s a significant fill rate advantage over their competition. The GeForce 6600 GT offers twice the fill rate of an X600 XT and the vanilla 6600's fill rate is 50% higher than the X600 Pro's.
Things aren't quite as uneven in the memory bandwidth department. Still, the 6600 GT delivers 36% more memory bandwidth than the Radeon X600 XT thanks to a higher memory clock. Since GeForce 6600 board vendors will have considerable freedom setting memory clock speeds, I can't comment on how well the vanilla GeForce 6600 will stack up against the Radeon X600 Pro. Both cards have a 128-bit memory bus, so it will come down to clock speeds. NVIDIA's board partners should have no problems matching the X600 Pro's 300MHz memory clock.
As far as board characteristics go, the GeForce 6600s look potentially well-behaved. Both cards can get by with a single-slot cooler, which is especially impressive for the 500MHz 6600 GT. Neither card requires an auxiliary power connector, in part thanks to the extra power delivered by the PCI Express interface. However, AGP versions of the 6600 GT may require a little extra juice.
Although it's not an option on the vanilla GeForce 6600, 6600 GT owners will be able to run a pair of cards in SLI. NVIDIA has already announced SLI for its GeForce 6800 family, and you can read more about the graphics card teaming technology here.
Running a pair of 6600 GT cards in tandem should yield a nice performance boost, but there's a catch. You'll need a motherboard with two PCI Express graphics slots. Currently, the only mobos available with dual PCI-E graphics slots are workstation-class dual Xeon boards that are priced well over $500. Xeon processors aren't exactly cheap, either. That's hardly a practical platform for mid-range SLI with $199 graphics cards.
Fortunately for NVIDIA, they're also in the chipset business. It seems entirely likely that NVIDIA has nForce core logic in the works with enough PCI Express lanes for two PCI-E graphics slots. When that chipset will arrive is anyone's guess. Until we see reasonable-priced single-processor boards with dual PCI-E graphics slots, SLI probably isn't going to take off with the GeForce 6600 GT.
It's really a shame that more affordable SLI platforms don't exist, because a pair of GeForce 6600 GTs could be scary fast. SLI also offers an incremental upgrade path that's sure to intrigue users with an aversion to dropping a lot of cash on a single graphics card purchase.
Since the GeForce 6600 family is targeted at mainstream consumers, NVIDIA is also hyping the cards' advanced video features. The 6600s support advanced de-interlacing, inverse 3:2 pull down, WMV9 acceleration, and motion estimation, just like the GeForce 6800 family. These video features could be particularly valuable should NVIDIA offer a version of its Personal Cinema based on the 6600 family. My home theater PC beckons.