[问题]初进系统登录界面时，屏幕分辨率为640*480可能更小，看不到登录框，怎么办？

[eastmountain]

问题如上：
不过进入系统后屏幕分辨率又变成了1024*800

我的xorg.conf:
Section "InputDevice"
Identifier "Generic Keyboard"
Driver "kbd"
Option "XkbRules" "xorg"
Option "XkbModel" "pc104"
Option "XkbLayout" "en-us"
EndSection

Section "InputDevice"
Identifier "Configured Mouse"
Driver "mouse"
EndSection

Section "Device"
Identifier "Configured Video Device"
Boardname "ATI Radeon (fglrx)"
Busid "PCI:1:5:0"
Driver "fglrx"
Option "VideoOverlay" "on"
Option "OpenGLOverlay" "off"
Screen 0
Vendorname "ATI"
Option "MergedFB" "off"
EndSection

Section "Monitor"
Identifier "PHILIPS 107B5"
Option "DPMS"
HorizSync 30-86
VertRefresh 50-160
Vendorname "Plug 'n' Play"
Modelname "Plug 'n' Play"
modeline "640x480@60" 25.2 640 656 752 800 480 490 492 525 -vsync -hsync
modeline "640x480@72" 31.5 640 664 704 832 480 489 491 520 -vsync -hsync
modeline "640x480@75" 31.5 640 656 720 840 480 481 484 500 -vsync -hsync
modeline "640x480@85" 36.0 640 696 752 832 480 481 484 509 -vsync -hsync
modeline "800x600@56" 36.0 800 824 896 1024 600 601 603 625 +hsync +vsync
modeline "800x600@72" 50.0 800 856 976 1040 600 637 643 666 +hsync +vsync
modeline "800x600@75" 49.5 800 816 896 1056 600 601 604 625 +hsync +vsync
modeline "800x600@85" 56.3 800 832 896 1048 600 601 604 631 +hsync +vsync
modeline "800x600@60" 40.0 800 840 968 1056 600 601 605 628 +hsync +vsync
modeline "832x624@75" 57.284 832 864 928 1152 624 625 628 667 -vsync -hsync
modeline "1024x768@85" 94.5 1024 1072 1168 1376 768 769 772 808 +hsync +vsync
modeline "1024x768@75" 78.8 1024 1040 1136 1312 768 769 772 800 +hsync +vsync
modeline "1024x768@70" 75.0 1024 1048 1184 1328 768 771 777 806 -vsync -hsync
modeline "1024x768@60" 65.0 1024 1048 1184 1344 768 771 777 806 -vsync -hsync
modeline "1024x768@43" 44.9 1024 1032 1208 1264 768 768 776 817 +hsync interlace +vsync
modeline "1152x864@75" 108.0 1152 1216 1344 1600 864 865 868 900 +hsync +vsync
modeline "1280x1024@75" 135.0 1280 1296 1440 1688 1024 1025 1028 1066 +hsync +vsync
modeline "1280x960@60" 102.1 1280 1360 1496 1712 960 961 964 994 -hsync +vsync
modeline "1280x960@85" 148.5 1280 1344 1504 1728 960 961 964 1011 +hsync +vsync
modeline "1280x1024@60" 108.0 1280 1328 1440 1688 1024 1025 1028 1066 +hsync +vsync
modeline "1280x960@75" 129.86 1280 1368 1504 1728 960 961 964 1002 -hsync +vsync
modeline "1400x1050@60" 122.61 1400 1488 1640 1880 1050 1051 1054 1087 -hsync +vsync
modeline "1400x1050@75" 155.85 1400 1496 1648 1896 1050 1051 1054 1096 -hsync +vsync
modeline "1600x1200@65" 175.5 1600 1664 1856 2160 1200 1201 1204 1250 +hsync +vsync
modeline "1600x1200@60" 162.0 1600 1664 1856 2160 1200 1201 1204 1250 +hsync +vsync
modeline "1792x1344@60" 204.8 1792 1920 2120 2448 1344 1345 1348 1394 -hsync +vsync
modeline "1856x1392@60" 218.3 1856 1952 2176 2528 1392 1393 1396 1439 -hsync +vsync
Gamma 1.0
EndSection

Section "Screen"
Identifier "Default Screen"
Device "Configured Video Device"
Monitor "Configured Monitor"
Defaultdepth 24
SubSection "Display"
Depth 24
Virtual 1856 1392
Modes "1024x768@75" "800x600@85" "800x600@60" "800x600@75" "832x624@75" "800x600@72" "1024x768@85" "800x600@56" "1024x768@75" "640x480@85" "1024x768@70" "640x480@75" "1024x768@60" "640x480@72" "1024x768@43" "640x480@60" "1152x864@75" "1280x1024@75" "1280x960@60" "1280x960@85" "1280x1024@60" "1280x960@75" "1400x1050@60" "1400x1050@75" "1600x1200@65" "1600x1200@60" "1792x1344@60" "1856x1392@60"
EndSubSection
EndSection

Section "ServerLayout"
Identifier "Default Layout"
screen 0 "Default Screen" 0 0
EndSection
Section "Module"
Load "dri"
Load "v4l"
EndSection
Section "ServerFlags"
EndSection

[losant]

不知道，我的在登录和进入系统后的显示都没有变，而且只能显示600*480，超级郁闷。