Reasons for this are from settings to drivers to some malware infection. Since the shop set it up, back to the shop and have them set it up again.
Bob
When I boot up I will see the start up screen briefly and then the screens go black. Everything is going on behind the black screen. If I turn the monitor off and on again, I will get another glance at the desktop. I took the CPU in and had diagnostics run and everything passed. It was set up with two screens in the shop and worked, but when I brought it home and connected to my two Acer monitors I had the same problem. I am lucky everynow and then and I get ge the screen to stay on. I now have the right screen black, indicating no signal. Help!
nln8

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