Maps and Memory

I am very sure the new map overwrites the existing map unless you tell it to store to a memory stick present in the unit.

The new map does overwrite the previous version. Bit each new map is slightly larger than the last. I have been tracking the free space on my 660 since I first bought it.

Here is a post I made in another topic:

For the record, this was the amount of free space on my 660 with each of the mapsets I've installed:

I was able to install the update without having to delete any files.

Depending on which model you have and what you have loaded on it, YMMV.

If you run Garmin's official update, the maps will in fact over write the old ones. But the last few versions have been slowly increasing in size, so it is reasonable to believe that eventually all of North America won't fit on some NUVIs anymore.

My old 360 had enough space for Canada, the United States, Mexico, some of Europe and some Bluecharts. x70 series NUVIs (that come with Europe AND North America) will be able to hold pretty much anything indefinitely, as I think they have 4 gb of ram.

I am looking forward to seeing how much space the NUVIfone M20 has and how it deals with the loading of maps.

I came to the same conclusion. That's why I started tracking the remaining free space with each new map install.

One way you can free up a lot of space is by simply deleting all the vehicles you don't use. If you have every Garmin vehicle and maybe a few customs loaded onto your GPS, it can easily total around 200 MB.

In addition to the vehicles, JPG, GPX,and other files can use up a lot of memory.

Because the space taken by these other items can vary greatly over time, I think it would be better to compare the sizes of the map files of various versions than to track how much memory is left after each map update.

Can you erase old maps for new ones on a 885T? North America maps.

I asked this question of Garmin when I wanted to buy my first map update. They said it overlaps old one and does not add to mb total.

How do you find out how mush free space you have in your unit?

All the space in my unit is mush free. I guess the huskies ate it all.

Just kidding.

The way I do it is: hook GPSr to computer and go to (My)Computer and right click the units drive letter, then click properties.

I have had no problems installing North American Maps.

However, to be safe, I made a point of deleting everything other than the English and American voices. I really doubted that I would be trying to navigate in Turkish or Polish. These files can be anywhere from about 1 Meg to 16 Meg.

I also keep all POIs on my SD card. They're easier to manage and also put no load on my memory. (GPS Memeory that is. My personal memory is another thing)

The map file size has to increase as more streets, roads, and POIs etc. are added to the map,

Here are the sizes of the main map file, gmapprom.img, on my Garmin 255W for two versions:

2010.10 1,150,464 KB
2010.30 1,182,080 KB

When I installed the .30 version the .10 version was automatically deleted.

Now that's funny right there I don't care who you are!

To find out how much space you have left, plug the GPS into your computer and open up the computer line after clicking on the icon on the bottom left of the task bar.
This will show you all the drives on the computer. One will be the GPS. Click on it and then click "properties. This will show you a pie chart of the drive with used space and free space.

Okay..I made a mistake..it's " how much "..

Thanks for the answers!

Kevin M.