I'm interested in this too.  u-Blox delcares:

"Coldstart:
In Coldstart, the receiver has no knowledge of its last position or 
time. This is the case when the RTC has not been running, no valid 
ephemeris data or almanac data is available (This is the case if the 
receiver has never been navigating or the battery backup memory is lost). "

They then go on to spec typical coldstart time to first fix as being 
around 45 seconds for some of their Antaris units with max around 65 
seconds or so.

If that's true then it seems the 12 minute download is not required.  Of 
course, it may just be "marketing-speak".



Robert Rolf wrote:
> Thanks for the info Zik.
> 
> Some of the newest chip sets (SiRF III) can warm start in under 2 seconds.
> Quite amazing to have valid NMEA sentences popping out 2 seconds after a power up.
> 
> Some GPS's allow the user to input date/time/location to shorten the cold start time.
> 
> My question was specific to cold starts where all of the above are unknown and a full
> almanac needs to be downloaded.
> 
> Robert


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