Maybe I didn't understand correctly, on my ACER Aspire One ZG5 I can set 1024x768 "manual setting" whether I use intelGMA or VESA, but it is not good because the screen is too long and AmiStart for example comes out of the screen.
The problem is that the screen of ACER Aspire One ZG5 does not support 1024x768 resolution, the Screen of ACER Aspire One ZG5 is too small because it is set for 1024x600 resolution.