I've been recently trying to restart using a circa-2008 GPS I own, a Magellan Triton 500. Back when I purchased it, it was so frustrating to use that I gave up. It's time for a rematch.
There used to be a english forum with lots of information on these, but it closed some years ago. Whatever was in this forum is lost forever (and no, the web archive didn't save the posts, only the thread subjects).
There are still tidbits of info scattered here and there, however. Many in russian and german though, which requires running them through a translator, with mixed results. I might try to put a comprehensive page in the future in this blog in case they go down, too.
In the mean time, here is the best hack available for this unit. I found an interesting post in a German board that explains how to flash an unofficial driver for the SiRFstar III GPS chip that updates its software from GSW 3.2.4 to 3.5.0 and it increases the unit's sensitivity considerably. The details are here:
http://www.magellanboard.de/viewtopic.php?f=35&t=4343
Here is how to do this.
1. Download this file here:
http://maps4me.net/tools/Triton500_UPD1.95_SIRF.zip
P.S. maps4me offers many maps for the triton for a one-time download fee, I suggest you check it out.
2. Extract the zip file.
3. Turn OFF your GPS (this is important, if it's already turned on when you plug it in, the GPS driver will fail to install)
4. Run MgnFwUpd.exe
5. NOW plug your GPS, turn it on, and run the update. It takes at least 30 minutes to complete.
6. Tada! The about -> version page should show GSW3.5.0 for SiRF.
I've tested this on Windows 8.1 and it still works even if the software was probably designed for XP.
For advanced users: If you don't want SiRF 3.5.0, there is a way to update from 3.2.4 to 3.2.5 using official Magellan code. I requires downloading the latest firmware update to 1.95 from Magellan, running their update, finding out the temporary directory where it extracts its data, then modifying MgnFWUpd.xml to uncomment the line mgnFWGpsChipUpdate version. I tried it but didn't find 3.2.5 to be very useful.