OS: RedHat 7.3, Debian Sid

Kernel: 2.4.19-pre10-ac2 (what a mouthful)
I run a very recent kernel because the biggest thing lacking on this machine is full ACPI support. I tried a couple of 2.5.x kernels with Intels ACPI stuff and, though I finally had battery status, the system was (not surprisingly) extremely unstable. A worthy experiment, but back to 2.4 for now.

X: XFree86 4.2 (now 4.3)

As best i can tell, these are the parts inside. There are several different 1700 series notebooks, so YMMV.

Power Management
First off, like many newer notebooks, this machine is ACPI only. As ACPI on Linux is still very much a work in progress, some things work and some don't. The only non-working thing that matters to me is the lack of battery status. (I'm now using a 2.4.22 kernel with Con Kolivas kernel patch set and many more ACPI functions are now working, including battery status and charging state.) Other than that, it runs cool enough, the CPU throttling works, the LCD blanks and you can check the thermal status. The lid sensor and power switch do register ACPI events so if you grab a copy of acpid you can take a user-defined action on those events (like powering off when pushing the power button.) Here's a quick script which I use to warn me of low power status and to shut the machine down cleanly if necessary: acpi_monitor.pl

Video: ATI Radeon Mobility M6 LY Rev 0 (8MB Video RAM)
Works fine with XFree86 4.2 or 4.3 @ 1024x768. Currently running XFree86 4.3.
You may need to add "VideoRam 8192" to the appropriate "Device" section of your XF86Config. My XF86Config-4 is here for reference. It also shows one way to get a second mouse working and define an external monitor. I haven't yet determined if S-Video out works. Update: S-Video out does work, see below.

The only caveat is that if you switch from X to a virtual console, X will lock up completely if you try to switch back. It's not a complete lockup as you can still ssh in from another machine and shut down.
UPDATE: Grab a recent copy of the Radeon driver from dri.sourceforge.net You'll need XFree86 4.3, for the current snapshots, I think.

Tv Out: After much fiddling, it does work. What you need to do is:

1. Grab a copy of atitvout.
2. Temporarily change your driver in XF86Config4 from 'radeon' to 'vesa'.
3. Change resolution to 640x480 (800x600 may work, have not tried).
4. Reboot with the TV plugged in.
5. As root run 'atitvout -f t'

When you are done, 'atitvout -f l' (that's an 'ell' not a one) should get you your LCD back.

Touchpad
Works fine. Tap to click works also. This can be configured with tpconfig from Synaptics, or the more full featured driver written by Stefan Gmeiner.

Sound: 82801CA/CAM AC'97 Audio (rev 1)
Works. Sound is good for a notebook, although underpowered. I'm using the i810 kernel module.
The volume buttons on the keyboard don't work (or even register keycodes using scankey), so you'll need to use a software mixer.
Update: The acme Gnome 2.2 package enables the volume buttons.

DVD/CDRW
DVD works great, burning works fine at 4X.
As the other guy who wrote a 1720 page points out, you'll probably need to make a symlink to the real device that is your DVD player:

ln -s /dev/scd0 /dev/dvd

USB
Works great. If you build a custom kernel, use the main UHCI driver and not the alternate one.

PCMCIA
The two things i've thrown at it (A NIC and a wireless NIC) work flawlessly.
Update: At least one card, A USR modem, fails to init. about 1/4 of the time. My guess is that the BIOS sets up IRQ's and memory at boot, and sometimes doesn't get it right. The BIOS is very limited and there is no way to tell it how to allocate resources. Getting the modem to work is at times a 10 reboot process. And the built in modem is a piece of shit -- at least, The Linux drivers suck.

FireWire Port
?????

The modem and the built in ethernet NIC gave me some trouble

NIC: /proc/pci shows this as a Intel Corp. 82801CAM (ICH3) Rev. 65
This was the biggest pain in the ass. It detects as an eepro100, but every driver I tried in various kernels either eepro or eepro100 had moderate to serious problems with timeouts. It got quite tedious doing "ifdown eth0; ifup eth0". I downloaded a 20MB kernel source file whilst resetting the NIC every 300KB or so!! Once I found the right driver though, it has been fast and reliable.
The only driver that has worked for me is Intels e100 which at the time of this writing can be found on Intel's download finder page

Modem: Conexant HSF 56k HSFi
It's some winmodem variant, and it's a P.O.S. RPMS and source for the drivers were available, but the company providing them has now decided to charge. Given the crappy state of the drivers when I last used them, I don't believe the price to be worth it and I will no longer link to that company.

Thanks to chris at certifiedparts.com who donated a nice 56k USR pcmcia modem to replace the worthless built-in one.

None of the misc. extra buttons on the keyboard send scancodes at all. Neither does the little arrow thingie below the touchpad.
No hibernation ability yet. Maybe we'll see that in a 2.6 kernel.
If you happen to leave the AC adapter plugged into the notebook but unplugged from the wall and you have ACPI debugging on, you'll fill up your log files :-)

This is a pretty snappy little machine and quite inexpensive too. All the major things work and it is quite solid in terms of construction as well as software stability. The two negatives are: 1) the LCD screen which looks washed out unless you're viewing it from *exactly* the right angle. 2) The left and right mouse buttons on the touchpad are waaaaay too hard to push. Update: One year later and the touchpad buttons have begun to wear out entirely. They are now extremely insensitive.

Thanks to all the random folks whose archived conversations on Google Groups helped me to figure all this stuff out. And, of course, thanks to all the coders, writers and idealists who make all this cool Free Software.

• http://www.math.ohio-state.edu/~ccunning/compaq.html
• http://home.earthlink.net/~mtomasv/1720us.html -- (if it looks familiar, I stole the layout from Eric's Resume and Tomas stole it from me ;-)