pismo start-up problems


i have a powerbook pismo 500 that has developed a problem. when i try to start it, the hard disk spins, power light on, but the screen stays black (blank?). after trying everything i could think of, i found out that it WILL start-up fine if the small reset button on the back is pressed first. unfortunately, you have to do this everytime. it also seems to be running pretty slow. i can't think of anything that might have caused this... no recent software installs, or ram upgrades or anything... just out of the blue... did a search and the best i can find is a sleep mode bug, which doesn't seem to be what's going on.

anybody heard of anything like this?

any advice is appreciated... i need my mac!

hmmnn. well no one is responding to this, but i did find some references to replacing a pmu card, which is inexpensive, so i guess i'll try that. since i have to press that button to make the thing work... also, i booted up in os9, and got an error -- "cache memory problem." if anyone knows about this stuff, i'd sure appreciate any thoughts...