My Power Mac 7300/200 has problems coming out of sleep mode. If you put it to sleep, you can't wake it, it just freezes. If I let it go to sleep by itself, it would wake normally until recently. Now it freezes after sleeping no matter how it went to sleep requiring power off/on to reboot. It is running OS 8.0. How can I get sleep to work properly? Does it work properly under OS 8.5?