Monitor issue

[bigbw]

When pc starts monitor shows splash screen before log on screen for a second or two and then goes black..  Windows is starting normally as I can hook up another monitor and it works fine.. If I turn monitor off and back on, I get the same screen for a second or two and then black..  Same thing happens if I try to go into bios, I get first bios screen for a second or two., If I turn pc and back on a few times, monitor will eventually hold the picture and work fine.. I can turn pc off and on after that and all is normal.. Only seems to happen after PC has been off for a couple of hours or more..   This is an old monitor and may just be wearing out, but any help would be appreciated.. 

[Prométhée]

Hello
unfortunately may be at the end of life, apart from going to see a specialist, may not be much to do!
In addition, the repair could be almost as expensive as changing it!
Is this model?

https://support.hp.com/us-en/product/hp-s2031a-20-inch-widescreen-lcd-monitor/4190161/product-info

if yes, it is specified vga and dvi-d, try if possible to connect it otherwise in dvi if it is connected in VGA for example!

[bigbw]

that is the one.. I have tried both VGA and DVI-d  connections with different cables,  multiple power cables, and different video cards  as well as on board video..  I suspect you are correct re end of life. but once I get it working it is great.. I can leave it on for days at a time with no issues..  Suspect I will just keep it as a spare.. 

[Prométhée · Accepted solution]

yes, indeed it can be random, and work like that, until the moment when it will not turn on at all!
Unfortunately, from here, there is nothing we can do, it is most certainly an internal concern, maybe not much, but only a professional could check, and again!
Please mark the subject, if the answer is suitable

[bigbw]

I found a main board on Ebay for under $20, might give that a shot.. It is just used as a spare now..