Home : Compaq Presario 2100US

How to make Redhat 7.3 work on a Compaq Presario 2100

I wrote this page because a quick google search returns less than one might like to know about running Linux on this laptop. One hopes, of course, that this article will change that.


Here's what my Presario 2100US came with:
I think all other Presario 2100US laptops are mostly the same as this one, except for minor variations in memory size, CPU, and stuff like that.

Getting it all going

This page will only discuss Redhat 7.3, because it's what I use. I hope that the advice here transfers easily to other Linux distributions.

The initial install

Redhat 7.3 will install correctly on this laptop without requiring any special tricks. This is in contrast to some other (unnamed) laptop brands which require a patched kernel even to boot.

Here is the kickstart file that I used for my initial installation (root password has been changed to protect the innocent). The following tidbits in the first screenful of that file are all you need:
The resulting Redhat installation is already minimally functional, but can be improved in several ways as discussed in the sequel.

Compiling a kernel

If you want nice features like battery monitoring and LCD brightness control, then you need to compile your own kernel.

I recommend downloading kernel 2.4.23, which includes ACPI power management functionality built-in. The ACPI patch is required for any halfway serious use of this laptop, because the laptop does not support APM at all. If you want, you can use my kernel config file as well.

Save all the files in /usr/src, and run the following commands to build a kernel:

cd /usr/src/
tar xjvf linux-2.4.23.tar.bz2
cd linux-2.4.23
cp ../2100us-config .config
make oldconfig dep clean rpm

If all goes well, then you'll get kernel-2.4.23-1.i386.rpm, which you can then install (rpm --install), making sure to edit /etc/grub.conf afterwards to add a boot entry for the new kernel.

After booting the new kernel, the LCD brightness controls (Fn-F1/Fn-F2) should work, and the battery information will be available under /proc/acpi/battery. GNOME users can use this patched version of the GNOME 1.4 battstat_applet to display battery status information in the GNOME panel.

Optimizing XFree86

There is now a patch for XFree86 4.3.0 that enables accelerated Radeon driver support for the IGP 340M graphics card in this laptop. The accelerated Radeon driver is much faster than the default VESA driver included with Redhat 7.3, and I highly recommend using it.

I have built XFree86 4.3.0 against this new patch and made the rpms available for download. You can also download my XF86Config-4 file, which uses the radeon driver and also includes added support for USB mice.

For DVD playback, you will need to configure enough video memory in the BIOS to allow the driver to use hardware video overlay. 32MB of video memory is required for video overlay support in 32-bit color mode!

3d acceleration

People who are interested in hardware accelerated 3d support should take a look at Hui's 3d patches against the current CVS version of XFree86. You also need to install the kernel module which is provided on that page. I have not personally tried any of this software, since it is quite bleeding edge and I don't use 3d myself.

Video outputs

Both the external VGA output and the S-Video TV output work using the atitvout program, provided that you take note of the following:
  1. You must run atitvout with the -f option to force "Rage Mobility/Rage 3D Pro LT mode" (not Radeon/R128 mode).
  2. In order to use TV output, the TV must be connected to the laptop before booting up. (This is not needed for external VGA output, only for TV output.)
  3. The computer cannot simultaneously display video on both the LCD and the TV output. So you must choose between -f l for LCD or -f t for TV. The -f auto option does not work. (n.b.: The external VGA output can be simultaneously used with either the LCD output or the TV output, with -f lc or -f ct.)

CD burning

The cdrecord program (included with Redhat 7.3) works out of the box on the laptop with one exception: it cannot blank CDRW discs without crashing. Fortunately, the cdrdao program (also included with Redhat 7.3, although not installed by default) can blank CDRW discs on this laptop. The incantation is:

cdrdao blank --device 0,0,0 --driver generic-mmc --blank-mode minimal

If you want to blank the entire disc instead of just the table of contents, use --blank-mode full instead.

The power button

In Windows, the power button on the laptop initiates a clean shutdown and then turns the laptop's power off. To accomplish the same effect in Linux, install the acpid rpms and copy this file to /etc/acpi/events/power.conf. Then reboot, or restart acpid (service acpid restart), and the power button should launch the shutdown procedure when pressed.

Disk drive optimization

The hard disk and DVD/CDRW drive in this laptop support UDMA33 operation in Linux, but Redhat by default uses PIO operation. Switching to UDMA33 mode provides a substantial performance boost.

To use UDMA33 mode, edit the file /etc/sysconfig/harddisks and uncomment the USE_DMA line. Then copy that file over to /etc/sysconfig/harddiskhdc. The copying is required because Redhat 7.3 will not apply DMA to the cdrom unless there exists a specific sysconfig file for the cdrom drive.

Note that an updated kernel is required in order to obtain UDMA33 operation.

The Winmodem

You can use the on-board software modem in Linux using the Linuxant linmodem drivers. Follow the directions for the HSF (softmodem) driver. Note: the driver from the Linuxant web site is deliberately limited to a data rate of 14.4k, unless you pay them $15 for the full version.

Fortunately, the 2002-12-26 beta version of their driver supports 56k speeds, is free software, and works with this laptop. I have posted this beta driver online at this location. To use these drivers in redhat, install the hsflinmodem package along with the kernel-source package, and run the included hsfconfig program to set up the module configuration. Note that the old beta winmodem drivers are somewhat unstable and do tend to crash under heavy load. It is up to you to decide whether they are worth using.


Region Playback Control (RPC)

The QSI SBW241 DVD drive in this laptop (like all new DVD drives) is RPC-2. If you wish to play DVD movies from multiple regions, it is highly recommended that you install the RPC-1 firmware patch for this drive. Installation of the firmware patch, unfortunately, requires that you boot into DOS from either floppy disk or hard disk.

If you're only ever going to play DVD movies from a single region, it's easier to get the regionset program and set the drive to the region you want.

Keyboard layout

Here is an Xmodmap file which remaps Caps-Lock to Ctrl and Windows-key to Compose. I find this remapped layout much more usable than the default layout. To use this file, copy it to ~/.Xmodmap and log out and back in to X.

Sub-pixel fonts a.k.a. ClearType (tm)

If you want beautiful sub-pixel antialiased fonts on your LCD screen in linux, the easiest way is to install Redhat 8.0 or above, which have this feature built in.

There is a Sub-Pixel HOWTO, but I have not been able to get any of the methods in it to work in Redhat 7.3.


Untested, but should work in Linux:
Things that don't work in Linux yet:

Other links

TuxMobil (formerly Mobilix)

Linux on Laptops

Copyright © 2003 David Jao (djao@dominia.org).