In case any one still searching for an answer if you have Gameboy Pocket / Color / GB Boy Colour
You need special kind of batteries 1.6V AA or AAA versions / Extra-high capacity 1500mAh / 2500mWh Ni-Zn rechargeable batteries.
God hear you.
Just got my gb boy colour and everdrive x7 gb keep reseting.
I purchased 1,5V and 2850mah batteries non rechargeable from Amazon, I didn't find any with 1,6V
Lets see what happens
EDIT: Okay, before I get the new batteries I just formatted the sd card and now I'm able to reach at least the OS menu, but when I start a rom, when the console resets, I got back to the OS menu and not the rom I loaded
EDIT2: Okay, this got interesting
I'm only able to boot up into the OS if I format the micro sd selecting 8192 bytes. Any of the other settings will lead my to a fail
The micro sd is a amazon sandisk 16GB class 10
EDIT 3: after trying to change the partition size with minitool partition wizard, no success, in fact, I can't even now boot up again the OS even using the windows formating tool . Trying now a slow format with windows tool selecting 32 KB
FINAL EDIT: Well, happy ending it seems. Took my Everdrive GBA 32GB micro sd. Formatted in windows in a various ways, until I tried 8192 option. Finally loaded a rom and working perfectly.
The good news is that now I have a lot of baterries for other stuff xDDDD
SAD EDIT: After a while of playing, os loop again. Checked in a ags 101, and there, it worked
So it seems that the SanDisk red class*10 micro sd give some problems to the gb colour.
MORE: Received the NON rechargeable 1,5V and 2850 mah batteries.
Works like a charm, after a 32 kb format: SLOW format