White Screen after booting with iMac G5

[flatjuba]

Anyone know why this is happening?
It boots but it goes directly to whitescreen....There is a ding sound when push the power button.
Thanks

 

[galgot]

Mmmh... these are the ones that had bad capacitors, and had to be changed at one time. Do you know if it had been done on this machine ? Check the capacitors (cans) for swelling and or leakage.
Maybe try a SMU reset, it's a button on the main board. The thing is very easy to open.
Check first response here :

RÉSOLU : See LEDs, what is the problem with this model not booting up - iMac G5 17" Model A1144

blake, here is what Apple says "The SMU (System Management Unit) is a microcontroller chip on the logic board that controls all power functions for your computer. If your computer is experiencing any power issue, resetting the SMU may resolve it. The SMU controls several functions, including...

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