当我尝试在 ubuntu 12.10 中执行 ctr-alt f(1-6) 时，我只会看到黑屏，光标闪烁，但没有登录提示。有什么想法可能出错了吗？这是使用 amd radeon 5850 显卡的全新安装 12.10。我在 /etc/default/grub 中尝试了不同的方法，但目前我使用以下方法：
# If you change this file, run 'update-grub' afterwards to update
# /boot/grub/grub.cfg.
# For full documentation of the options in this file, see:
# info -f grub -n 'Simple configuration'
GRUB_DEFAULT=0
#GRUB_HIDDEN_TIMEOUT=0
GRUB_HIDDEN_TIMEOUT_QUIET=true
GRUB_TIMEOUT=10
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash vga=normal"
#GRUB_CMDLINE_LINUX="vga=0x0376"
#RUB_CMDLINE_LINUX_DEFAULT="vga=0x014c"
#GRUB_CMDLINE_LINUX="vga=0x014c"
#GRUB_GFXPAYLOAD_LINUX=1600x1200x24
# Uncomment to enable BadRAM filtering, modify to suit your needs
# This works with Linux (no patch required) and with any kernel that obtains
# the memory map information from GRUB (GNU Mach, kernel of FreeBSD ...)
#GRUB_BADRAM="0x01234567,0xfefefefe,0x89abcdef,0xefefefef"
# Uncomment to disable graphical terminal (grub-pc only)
#GRUB_TERMINAL=console