Screen shows for 2 seconds then goes blank, if switch off and on again it shows for 2 seconds then off again.

you have input problems with HDMI 1 I would use 2 and leave it alone. You cannot repair this yourself.

Hope this helps.... Your monitor has an inverter issue. You know it's an inverter problem when:
1. Your monitor starts normally and displays the startup/desktop screen for a while.
2. Then it suddenly goes off, leaving a blank (black) screen or a very dim display.

To fix this black screen problem, change the inverter board (based on your monitor brand). Source(s): http://lcdmonitorrepair.annics.com

Have to try a defferent monitor to diagonais a problem but if its showing all your booting process after switching on nothing wrong with your monitor,but if keeps on restarting itself after boot up process ,I'd say that your system error corrupted. Need to reload your sytem.

The inverter boards on laptops are common failures. Depending on the age of the laptop it could also be related to a faulty LCD interface cable.

Did you swap the monitors to see if the problem follows or stays at the same video output port since you have dual monitors set up? Need verify before opening up the monitor.

Try to do this: Just before the Windows start up screen (after the bios loading) press F8 and log in at safe mode settings. If at this mode you can see your screen change the resolution settings at a lower set. Save and reboot normally. Now try step by step to increase your resolution. In case of a blank screen appears at a new setting, don't do anything; after some seconds the monitor will come back to the previous settings. Save and go on.

In case of a problem or clarification, don't hesitate to post.

Thanks and regards
Please kindly rate this solution
Stelios

i just finished repairing a 20 inch acer monitor that had the same issue.... you have to take it apart and examine the power supply side of the monitor. there are capacitors that go bad on that board. you can tell be feeling the tops of them... the feel rounded. replace the capacitors and put it back together and it will work fine

just an update...I have fitted a new cable (pc to monitor) and it has been on for 2hrs now so fingers crossed!

my first two ideas are....

1. Power setting/screen saver - this could be build into the monitor or a setting in the power options in the control panel.

2. improper setting for the monitor....this could be the refresh rate most likely.....right-click in a blank area of the desktop, go to properties, settings tab, advanced.....there should be an option in one of the tabs that has an option for refreash rate...make sure it is set to 60.....

If not one of these two things, than it is a faulty monitor......probably not worth getting fixed....hopefully still under warranty??