You can change the memory used to cache fonts glyphs, this allow you to use more memory to speed up the display.

Browse to
HKEY_LOCAL_MACHINE\SYSTEM\GDI\GLYPHCACHE

You can change the "limit" value :

4096 : slow down the display, but use less memory (default setting on Palm-size PC)

8192 : default value on Pocket PC, average memory/performances

16384: speed up the display, but use more memory, twice the default Pocket PC value...