CPU too hot

  1. Hi,

    iMac G5 + Leopard 10.5.6

    When my iMac G5 works in a very intensive way,
    it switch suddely in the sleep mode.

    It didn't happend under Panther 10.3.9

    I think it happend because the CPU is too hot.

    Do you know if it's possible to stop this switch ?

    TIA,

    Thierry