Hello,

i have this hp probook 6450b, when pressing power button only battery led is flashing 8 times. I already wrote full dump into bios chip, still the same. I resoldered power ic, i reflow chip, problem still exist, any help?

Ok the problem is from the adapter enable signal, there was a liquid damage, i fixed it now its turning on but no display.

Ok i found the problem, the ic u14 that supplies power to the vga is damaged, it has no output. I removed it and took the power from the 2 mosfets that powers the cpu, i took the lgate and ugate and soldered it to the pins of the 2 mosfets for vga, running for some time now, i hope it will work out.

Seems one mosfet got burned, so i soldered a wire from the cpu power coil to the video card power coil and disabled all other cpu cores inside windows to keep the power consumption low, hope it works this time.