[advancemame-users] pclock mode questions

[Alex U. <au...@is...>]

I've been successful using the 5-70 pclock mode settings, 10-70, & 20-70
 
But I don't understand what the pclock modes do, or are for. I notice that
in with the 5-70 set most games work fine, but when trying "TMNT" or "TMNT2"
they won't load, debug messages appear. If I set it to 20-70 these games
will work.
 
I'm using an ATI RAGE PRO Card. Can someone please help me understand
function of these pclock modes & how they are attributed to my ATI card?
 
Thanks very much!
 
-Alex