Continuing from the GTX 880 rumores specs, the guys at techreport have actually translated what the polish rumor said and made an analysis.
Apparently, the GTX880 isn't set to replace the 780 (Ti) because it isn't the top of the line card. That 880 is based on the GM204 parts while the full chip is the GM210 one. So, to put it another way, the 880 is the successor of the 680, which was a GK104 part.
Another thing they note is that it looks like there is an ARM processor in there, possibly a way to reduce draw calls and other tasks.
But, to put a big caution in regards to that rumor, they have also noticed that while the chip is rumored to use 230W, they polish leak says that it will only have 1 6-pix power connector. 1 six-pin connection gives about 75W + the PCIe slot that also gives 75W = 150 W, way less than the 230 W claimed that the card will use.
So... believe what you want 
Please excuse my bad English.
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