Category talk:Z60m
On a Z60m with 1280x800 screen and Intel graphics, I found that I can get the Linux framebuffer console to do full 1280x800 by passing "vga=874" on the kernel's options line. (Mode 873 is 8bpp; 874 is 16bpp; 875 is 32bpp but for some reason it causes a corrupted display.)
There's a good chance this'd work on a model with an ATI GPU instead of the Intel one, and there's probably an analogous fullscreen mode for the 1680x1050 screens too.