I couldn't find straight away the clock speed for 24bit mode; 16bit seems to be 80 MHz and 32bit 50 MHz. Principally you should get at least 1152x900@24bit, perhaps even 1280x1024 but then the board should be able to clock at least 80 MHz and give just about 50 Hz ni. Of course you need to have 4 MB onboard.
