X bother consoles

[maderios <maderios@gmail.com>]

Hi
After changing my hardware, a curious problem appeared with Wheezy and 
Squeeze.
When starting X from a console, the space of the other consoles seem 
"zoomed": the bottom of the console is not visible but I can always 
return the data from the keyboard, "blindly".
The command 'setupcon' restores the normal console  but when I restart 
X, console is disturbed again. The graphic card is a Nvidia Quadro600 so 
I tested kernel mode setting with the driver 'Nouveau': no problem. The 
console doesnt seem disturbed because of the framebuffer ..... By cons, 
as I have not intend to use Nouveau driver, I would like consoles back 
normal. I tested also with another graphics card (MatroxP690, vesa 
driver), same problem.
 I dont  understand how  X server can change the consoles display.
Thank you for any help, ideas / suggestions on this oddity.
Maderios