Question on multiple framebuffers

[Bob Alexander <bob@ngi.it>]

In this moment I have the following framebuffers compiled in my kernel:

radeonfb (supporting the ATI Radeon M9 chip of my laptop)
vesafb
vga16

Even though I use a GRUB kernel line with video=vesafb:1024x768-32
the dmesg shows that "something" is detecting the presence of the Radeon 
chip and the radeonfb gets used.

Is there a way to select the framebuffer I want or the only solution is 
not compiling the others ?

TIA,
Bob