dual monitor with integrated graphics

[mIXpRo]

hi ,
i'm using ubuntu 12.04 with intel integrated graphics card,
when i connect external display monitor to my laptop the screen goes black , not exactly once i connect the monitor but when i go to display setting to setup the resolution and the unity launcher place , then i click apply ,that's then when it goes black , i tried it on a friends laptop with also an intel integrated graphics card but there was no problem ???? why ????

[3Miro]

Which integrated graphics? Newer Intel HD 2000/3000 are much faster than say GMA4500 or older.

What is the resolution on the external monitor? Old video cards may struggle with high resolution monitors.

What interface are you using? VGA, DVI, HDMI?

[mIXpRo]

i'm using vga ,
with Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller
"Intel GMA 4500MHD" .

[mIXpRo]

additional info :
in ubuntu 11.10 there wasn't such a problem

[mIXpRo]

anybody ??
currently i'm using windows to use my monitor (what a shame :( )...