long pause before GRUB appears on ASUS G2S-B2

[Claude Jones <cjones@xxxxxxxxxxxxxx>]

I have an ASUS G2S-B2 laptop dual booting Fedora 8 and Vista.
When I start the computer, after the BIOS messages, the screen goes black with 
the exception of a single blinking dash in the upper left of the screen; 
after 20-30 seconds, the GRUB menu appears normally.
Any suggestions for what's causing the pregnant pause?
-- 
Claude Jones
Brunswick, MD, USA