Slowing Games Down To 50 Hz ?

Is there absolutely any way to slow games down to 50 frames per second ?

In retrocade, you can slow down or speed up which is cool, but with mame,
I've searched alot, and tried a bunch of stuff, but no luck yet.

The reason is because I'm in Australia, and we have PAL instead of NTSC.

When I use mame, the games are just a fraction too fast, which is why I
like using Retrocade, but obviously Mame has way more software.

Any help much appreciated.


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