I got a few emails from GDEMU owners, mostly asking for help with various issues, and I figured some additional clarifications are in order:
GDEMU does not remove region lockout. In other words, your Dreamcast will refuse to boot games from other regions just as it would refuse original GD-ROMs. This is on purpose, because…
Even patched to allow all region booting, some games will not work. This has nothing to do with GDEMU, it’s in the game code. Most games can be easily patched but some require a specific video output to be present – for example, USA region game might not work with RGB cable which is pretty much the default in EU. And there are a few titles that will just not work in non-native region, period.
In general it’s strongly recommended you stick to games for your region, and if you want to experiment then at least check how the original behave before you blame GDEMU. Seriously, get a clue, it’s starting to get annoying having to explain this over and over again.
Lately another issue popped up, apparently Dreamcast power supply unit can get a bit hotter when using GDEMU instead of the original drive. I never had that issue and it wasn’t reported by anyone else so far, but I suppose it’s possible that without the drive blocking off most of the direct route from the back of the unit (where the “gills” are) to the fan in front the PSU gets less airflow around it. I’ve been running GDEMU, it’s various versions, for many, many hours now, including no cover and open lid / not fully closed lid situations. I’ve never noticed the case to be strangely hot but I did not actually measure the temperature on the PSU itself. The report I got claimed it could heat up to just below 70°C. I don’t think it’s a problem, if you look at the design you will notice it never got any significant airflow either way and worked just fine. But for those worried I suggest you put a piece of cardboard screen fashioned to form a tunnel between the back, the PSU, and the fan. Do not remove that plastic cover though, it’s there to make sure the metal heat spreader is well insulated from mains.

http://gdemu.wordpress.com/2014/05/2...my-chinchilla/