Core Grafx II white screen

[Ergot_Cholera]

As the title. Swapped over all the main and RAM chips from a working original PC Engine and still no difference. Transplanted the removed chips into the PC Engine and it works.
Checked the cable between the boards for continuity and all is good.
Voltage regulator is outputting 4.99v.
I'm guessing that it is probably a via or trace somewhere, or maybe an SMD component, but everything looks okay.

[Keith Courage]

Try the hu6280 chip. If ram and card slot cable are good then the 6280 chip is usually the problem.