Hi everyone. First I have to say sorry for my bad english. When I fly on pmdg 737ngx, all displays go black. They are black like when battery is off and I can't fix it by switching battery off and on or anything like this. Autopilot continues flight on VNAV and LNAV, following the route and VNAV path normally, but all 6 displays are black. Only FMCs and secondary pfd are okay. Sometimes it happens to me on pmdg 777. I have pmdg 737ngx and 777 both SP1D and FSX acceleration. Any solution? Many thanks