Yesterday, 18 Sep 2014, Nvidia released its two new flagship cards from the Maxwell line of GPUs: the GTX 980 and the GTX 970, for an MSRP of respectively $549 and $329.
The 980 sports a grand total of 2048 CUDA cores running at 1126 MHz base clock which are able to reach 1216 MHz while in boost, and 4 GB of VRAM driven at a frequency of 1750 MHz by a 256-bit-wide GDDR5 bus. The memory interface thus allows the card a sample rate of 7 GT/s (you read that right) and, for the price, a surprisingly mediocre theoretical memory bandwidth of 224 GB/s, almost 100GB/s slower than the older Radeon R9 290X.
The 970 has 1664 CUDA cores clocked at 1050 MHz base / 1178 MHz boost, and retains the same memory amount and interface as its pricier sibling.
The most notable software characteristics common to the two are the new Dynamic Super Resolution Anti-aliasing method (Super sampling with a 13-tap Gaussian filter for resizing,) which can be used with any game in your library simply by activating it in the GeForce Experience panel, and Multi-Frame sampled Anti-Aliasing (MFAA).
Bad news for HDMI aficionados: there is no HDMI 2.0 support on either of the two cards, so you will still need a DisplayPort monitor to do 4k at 60 fps See update below.
But the real kickers are the TDPs of these two new specimens: a measly 165W for the 980 and only 145W for the 970, which allow both of them to feed off of 2x 6-pin power connectors and possibly make them the two most power-efficient cards yet in this price range.
As for physical dimensions, they both measure 4.376" x 10.5" (11,16 cm x 26,67 cm) HxL, with a dual-slot cooler.
The GPU's codename, GM204, indicates that we could witness in the future a situation similar to what happened with the GTX 680, where the flagship chip wasn't fully enabled and the unrestricted version of it would later be released as the GTX 780. Time will tell.
UPDATE: Nvidia's spec sheets for the cards have been modified, showing that they indeed support HDMI 2.0.