Hello! It's my first post here, so please be kind!

I got a defective console from a friend and I managed to fix it, it was just a power supply issue, but it seems to be from a diferent region. I tried NTSC/U and PAL games and it doesn't work, but using region free games it works fine. What's the easiest way to find out the region of the console (besides trial and error, of course

)?
I found some topics here about changing the region on the main board, but this console was updated very recently (with GOW 2). Is it possible to downgrade and change the region code? (ps. I don't know for sure the firmware level, but it's a falcon board and a samsung ms28 DVD reader)
Thanks in advance for your help!