hi,
i dual boot xp and mdk on a fujitsu s6120 laptop. at the time of lilo bootloader, mdk loading, mdk shutting down, or mdk w/ only cmd line (X not started), the screen seems to be only 800x600. definitely not the whole screen is used.
something wrong w/ my display? any suggestions?
thanks.

That would involve knowing what your video card (not mentioned in your post) you are using..

# Configuring X
Linux Hardware Compatibility HOWTO - video cards
The Linux XFree86 HOWTO
Configuring XFree86 for a Non-Specific Linux Distribution
Common X configuring tools:
Debian - dpkg-reconfigure xserver-xfree86
Mandrake - XFdrake
SuSE - sax2
Red Hat Linux 9: Red Hat Linux Reference Guide Chapter 7. The X Window System
Redhat 7.3 down - the setup utility leads to several config tools
Redhat 7.3 up - redhat-config-xfree86
You may have one or more of these tools:
XF86Setup
XFree86 -configure
Xconfigurator
xf86cfg
xf86config
xconf
ATI Linux drivers
If you need the nVidia driver, you want the Linux IA32 driver unless you just bought the new AMD 64 bit CPU

here it is from the tech specs from the fujitsu website:

Video

13.3" XGA LCD

Internal max: 1024 x 768 resolution, 16M colors

External max: 1280 x 1024 resolution,16M colors

Intel 855GM chipset with up to 64 MB shared memory using Unified Memory Architecture (UMA) delivers low-power, high-performance 2D/3D graphics, video, and display capabilities. Dynamic Video Memory Technology (DVMT) dynamically responds to application requirements and efficiently allocates the proper amount of memory (max. of 64 MB) for optimal graphics and system peformance.

AGP support

Simultaneous support for external monitor and internal display

Dual monitor support for graphics editing application

does that help?

Search for the Intel 855GM chipset in the HCL I posted previously and see if there is support.

Checking the Distro's hardware compatibility lists may provide hints as well.

Here are Mandrake links that may help.

# Mandrake links
Mandrake home page
Mandrake Users website
Easy urpmi config for Mandrake
urpmi mini-HOWTO
All You Ever Wanted to Know About Urpmi But Never Dared Asking Before
Maximum RPM
rpmfind
You didn't install the developmental packages? As root, command:
urpmi gcc
An Introduction to the Midnight Commander. You can install it by commanding:
urpmi mc
Midnight Commander home page

actually i just realized that the windows xp splash screen at boot time is also less than the full screen resolution i choose at 1024x768. so i guess this is not an mdk issue, but it probably is with my display somehow.
thanks.

Oh, yeah, you must be talking about using directfb on bootup since you are using Mandrake.

DirectFB Documentation and/or see man directfbrc

Play around with the stuff you see in /etc/lilo.conf, the stuff similar to append="vga=788" (making sure you can back up, boot rescue, etc., whatever you need to do in order to fix it back if it ain't right), then running /sbin/lilo to effect the changes.

LILO fails: Error messages and their interpretation
LILO mini HOWTO
Multiboot with LILO HOWTO
LILO, Linux Crash Rescue HOW-TO
Installing a bootloader

# Mandrake links
Mandrake home page
Mandrake Users website
Easy urpmi config for Mandrake
urpmi mini-HOWTO
All You Ever Wanted to Know About Urpmi But Never Dared Asking Before
Maximum RPM
rpmfind
You didn't install the developmental packages? As root, command:
urpmi gcc
An Introduction to the Midnight Commander. You can install it by commanding:
urpmi mc
Midnight Commander home page