The GPS folder holds the GPS Prediction Data for Fast Satellites Aquisition

Experiment:

I deleted the whole GPS Folder (Backed it up first of course)
Next I switched on Nuvi 3490
Nuvi took long to acquire satellites - 7 minutes To 3 meter Accuracy - Clear Sky
Connected Nuvi to Computer
GPS folder and all files were recreated by the Firmware.
Switched on Nuvi again.
Satellites were aquired immediately.
this proves our earlier suspicions that the GPS Folder does indeed hold the Predictive data.

Restored the "backed up" GPS Folder.
Switched on Nuvi.
Satellite aquision was immediate.