NVIDIA astonished us with GT200 tipping the scales at 1.4 billion transistors. Fermi is more than twice that at 3 billion. And literally, that’s what Fermi is - more than twice a GT200.
At the high level the specs are simple. Fermi has a 384-bit GDDR5 memory interface and 512 cores. That’s more than twice the processing power of GT200 but, just like RV870 (Cypress), it’s not twice the memory bandwidth.