Hello 

I need some help with Vostro 3250 i`m already trying to troubleshoot what`s with this PC,

So i had to reinstall system on this machine and i got this situation. i have some monitors 12 inch, 19 inch, 19 inch widescreen, 35 inch widescreen 

so i assembled pc turned on 12 inch display and booted it display got massage that analog signal was coming and after that there was black screen and that is all, i heard that cooler of Cpu was on high rpm, so it was not booting system (when turning on start button some seconds cooler is on high rpm, but when system starts booting Cpu cooler turns on low rpm), after that i tried on 35 inch display and there was same result, but on 19 inch display there was everything okay. after i tried to turn on PC without display plugged in and after boot i plugged in cable of display and it worked, but if cable was plugged in before booting or starting PC there was black screen, (it even can`t get me in bios), after i starter exploring i got some Video card to test if there was something with integrated but there was same result, i also tried to flash bios, upgraded it nulled it but there was nothing changed with result, i tried many ways to boot PC but it was only booting normally with 19 inch displays (widescreen too), with other displays every try was failure.

So please help me to decide what is with this PC why it is booting normally with 19 inch displays only and how to fix that problem.