keep getting this error on startup can anyone help me out????

agpgart: Maximum main memory to use for agp memory: 439M
agpgart: Detected Via Apollo Pro KT400 chipset
agpgart: unable to determine aperture size.
/lib/modules/2.4.29/kernel/drivers/char/agp/agpgart.o.gz: init_module:
Invalid argument
/lib/modules/2.4.29/kernel/drivers/char/agp/agpgart.o.gz: Hint: insmod
errors can be caused by incorrect module parameters, including invalid IO
or IRQ parameters.

any help much appreciated thanx