Jopo, I just figured this out myself, and it depends on what BIOS you're running. Myself, I'm using the Executor2 bios on my X2Pro....
Basically there's a feature added to the Executor bios that lets it SEARCH for Evox before launching the standard BIOS. How does this help? Well, the reason (at least why it was happening to me) that you were getting the error in 6 languages was that the xboxdash.xbe was a modified one, so when you turned your Chip off, it got all borked and doesn't load. What you need to do, is rename xboxdash.xbe to evoXdash.xbe, and rename msxboxdash.xbe to xboxdash.xbe.
Because the Executor2 BIOS will look for evoXdash.xbe BEFORE looking for xboxdash.xbe, you get yer EvolutionX dashboard and have no problems. When you disable your chip, the Xbox loads as normal, finds the xboxdash.xbe, which is the original, and loads with it like nothing ever happened.
The relevant part of the feature list from the Evox page is here:
|Auto Detect EvoX|
If you use the EvolutionX dashboard you will of course be naming it as xboxdash.xbe as default. Of you could use one of the evox hacked BIOS's where it looks for evoXdash.xbe. The problem with it being named as xboxdash.xbe is that there has recently been problems when using XBOX Live - whereas the dash was amended and files were altered thereby screwing up the function of your XBOX. With our new search feature the X2 BIOS will automatically search for evoXdash.xbe. If it does not exist on the hard drive it will then look for neXgen.xbe (see below) and then if not found will automatically boot xboxdash.xbe, therefore all components patched by XBOX LIVE are intact and everything will work just great.
The best part about this, is that no need for a boot disk!