Too little memory can not be solved in sys.txt.
Sorry. It can! By appointing some memory to iGO, but that is device dependable. So there is no general rule. It's a emergency solution, so to speak, and naming the wrong amount of memory can crash the device!
And in general sys.txt should be as short as possible. So that is memory saving after all.

From my experience, I know different solutions that work, however you have to pick one or more and give up some pleasant things.


1. The solution with the smallest impact on the operation of iGO: do not install a DEM-file. It has little use but needs a lot of memory. Limit also the maps you use. Why carry around 2GB of unnecessary maps?
2. Do not use speedcam warnings, therefor empty the speedcam folder, or at least, limit the speedcams to the ones you really need. Its no use for me wanting the speedcams of all Europe, always driving within a limited circle around my home.
3. Do not use TTS, but regular voices. Delete all TTS related files.
4. Do not use a large POI file.
5. Disable 3D view, (you may delete the 3dc and 3dl files too)
6. This is a bit tricky. Delete in data.zip/ui_igo8 all resolution folders that don't apply to your device. Be careful here!!
7. PNA devices do handle memory issues better. The iGO PDA builds are in fact simplified iGO releases, the most important disabled feature being TTS. Do not ask me what else is changed, but I do know that iGO PDA builds are less memory needing. So another tip could indeed be: use a PDA build (but loose TTS). I suspect the effect not being dramatically better, but hey, all little things could matter.

Another manner to solve this: http://www.navitotal.com/showthread.php?909-Double-din-2Din-GPS-How-to-install-thread

The final solution: get yourself another device with lots of memory aboard)

Everyone realizes these solutions are a choice. first pick the feature you want or need the least. Then the next one. And so on.

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About TTS and memory.
First see that your iGO build has TTS capability. The published sys.txt in post #1 shows a iGO non TTS capable line ([project] name="igo8_pda") together with TTS needed lines. Contradictory!
PDA builds do not suport TTS, PNA builds do.

Rule of thumb is : TTS needs 128MB. This does not mean that TTS won't work on devices with less memory (like mcowl's). Also some TTS voices are less memory greedy.
Also do not forget that Windows CE4.20 needs different DLL's than CE5 and higher
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