820-2915 doesn't pass post

[macitech]

Hi,
I have a 820-2915 doesn't pass post getting 3 beeps.
Changed memory tried both slots no good.
I plugged in usb mouse and it gets a light after I start machine.
Any ideas?
Tx

 

[dukefawks]

Voltage on L7330? If there is 1.5V then this will start to suck.....
You did test with known good PC10600 RAM I hope.

 

[macitech]

Yes correct memory.
Measuring .772 volts

 

[dukefawks]

oh shit, I had one that had low voltage like that.....never fixed it cause CPU issue.

Should be 1.5V there of course. Check enables at pins 16 and 17, if ok then dead U7300 or some component in the circuit. Also measure diode mode on L7330 to check for short.