I have problems with Lenovo G700 laptop. Recently I've replaced it's LCD screen, the original one got broken. Everything worked ok for about 2 weeks until I've installed some Windows 10 updates. After restart, screen went black, nothing could be seen. Screen was illuminated, but there was no picture at all. First I thought there is a software problem but when I connected laptop with external monitor, picture was shown (windows loaded normally). I even formatted the whole hard drive and obviously windows were not the problem here. One more thing I've noticed - even when I've got external monitor plugged in, Lenovo logo was NOT shown, I couldn't even get to BIOS - picture appeared when windows loading started.
It looks like there's some hardware problem, but I'm running out of ideas what to check next. On the other hand it seems quite a coincidence that hardware failure appeared just after I've installed windows updates. Screen guarantee hasn't expired yet, but I'd like to be sure that screen is defected. Is there something else to check first?
Thanks for any suggestion.