Intel recommends using straight video connections, the usage of adapters may interfere with the graphics multi-monitor functionality because you will be converting digital signal to analog.
You could try first installing the latest video drivers for your graphics controller: Download Intel® Graphics Driver for Windows 7/8.1* [15.36]
Thank you so much for your advise. I have tried the link provided but i get the error:
"The driver being installed is not validated for this computer. Please obtain the appropriate driver from the computer manufacturer. Setup will exit"
Afterwards i have tried to find the similar driver through dell. I run the driver detection software in the dell site.
2 drivers are found that should be updated.
- Chipset |Intel 8 Series Chipset Device Software Driver
- Video |AMD Radeon R5-240 / Radeon R7-250 Graphics Driver
The first seems that is installing, and the second one is failing. After the restart and repetition of the same procedure, both drivers are coming back and require updating. it seems that the card cannot connect with the two monitors.
Thanks for the assistance in any case.
Please bear in mind that once you install a video card on the system, this will electronically disable the on board graphics controller.
It seems to be an issue with the AMD Radeon R5-240 graphics driver.