Framebuffer experiences VESA vs. cyber200fb ?

I'm using the 2.6.6 kernel sources (debian)  to build an optimized 
kernel with framebuffer support. VESA works almost flawlessly, but i'm 
trying to squeeze a bit more performance out of it by using the 
cyber2000fb driver.

Questions:
1. Does it actually perform better then the VESA fb when it works?
2. I only get 640x480 to work with "spickles" in the background, other 
modes either give me a too low / too high verticaly or horizontal 
frequency and display nothing or garbage. Sounds like a timing problem, 
can these be passed through bootloader params?
3. Does it allow non standard modes? (specifically 800x480)
4. Are the video out and vga out separately controllable?

Thanks,

marcel

---+++---
Marcel van der Boom
HS-Development BV               --   http://www.hsdev.com
So! webapplicatie framework  --   http://make-it-so.info