I have a Dell Inspiron 6600 with an intel HD 2500. Since I got the computer, I have been running dual monitors using VGA and HDMI. Recently, this stopped working on boot up and when windows starts I only get the VGA monitor. I can get both monitors working again by going in the device manager and disabling then re-enabling the driver for the graphics card. When the computer is booting both screens work. It is only when windows start that I lose the HDMI display. I have updated the bios and have updated the driver both made not difference. Also the HDMI interface will not work even if it is the only interface connected at boot up. I would really like to get rid of this extra login step.
There is some more information I would like to verify from your system. Can you please post your DxDiag report?