The NV45 is mainly the same as the NV40, supporting DirectX 9.0c, with the PCI Express interface beeing the main difference. According to the Inquirer the production of this cards starts at one of the first days of April.
There will be two implementations of NV45 chips, as always. NV45 U implies Ultra and NV40 where Ultra will end up faster than 500, which is what Graphzilla is aiming for. Memory characteristics will be the same as the NV40, eight memory chips, 8x32BGA -144 GDDR 3 memory running at up to 600 MHz, 1200 MHz effectively. NV45 comes equipped with 256MB of 256Mbit GDDR3 memory, and not GDDR 2 like we suggested before. What's the difference? Even the vendors don't seem to know yet.
Nvidia has already sent over 500 boards to its customers to be able to prepare for the dawning of the Age of PCI Express.
Nvidia has put its PCI Express generation of cards under a Q2 hat but we suspect that NV45 might be announced together with NV40 so let's say it will be launched at Cebit in Hangover in March.