Some Work , Some Dont

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I just recieved some backups from a backup service: Silent Hill 2 + 3 , TigerWoods 2004 , Jak II , Need for Speed Underground , Madden 2004 , Prince of Persia. Only Problem is Silent Hill 3, Madden 2004 and Prince of Persia dont work! They boot allright, but after the Playstation 2 logo appers nothing happens. What could the problem be? bad burn , bootchip problem, what?

I´ve got a

30004R - model with an unknown no-swap mod-chip installed (works fine).

A newbie thanks for any help