HP dv2000 troubleshooting

[dcsinc72]

Hello,
I have an HP dv2000 (dv2125nr) that was having typical power up issues with the graphics chip. I had the motherboard repaired, but now the unit will not boot up WITH the AC adapter connected. It seems to work fine with just the battery. I've tried 3 different AC adapters, so it is unlikely that the adapter is the problem. Sometimes once the system boots with the battery, I can then plug in the AC adapter and it seems to function. I'm at a complete loss on this one and would love some helpful suggestions. Oh, I DID try another motherboard in the unit with the same results!

dcsinc

 

[dcsinc72]

Well, a follow-up with some additional data... Contrary to everything I've seen prior, the laptop will DIM the screen, usually to the point of unreadable, whenever AC power is plugged in! On battery, it works just fine. An external monitor works just fine either way. Only the onboard monitor seems to have issues. Could this somehow be an inverter issue of some sort?