When an NTSC game switches to 50 hz?

You can PAL fix most games by changing the following Hex.
Image the game to your HD first. I use Hiew hex editor but
most will do the job. Don’t ask me for a link because I can’t
remember where I downloaded it from :
In Hex Mode search for :

01 E4 03 A0 02 E4 01 A0 03

Change to :

00 E4 03 A0 00 E4 01 A0 00

Update and burn and that's it. Can take upto 5 minutes to find the Hex
code depending on your processor.

I PAL fixed Shenmue US and many others this way