The following is a list of drivers that I've used to get a Compaq C751NR working 100% under Windows XP. I've based this list off several I've ran across on the Internet, but with some differences: The wireless drivers have been modified to make the wireless LED indicator work correctly, the sound driver is a modified driver from Toshiba that makes the audio work 100% correctly (internal mic works, internal speakers mute/unmute on headphone usage, and the pitch of the audio isn't too low), and the touchpad driver is also from Toshiba (and a much newer version).

Some/most of these drivers are probably applicable to other Compaq C700-series laptops. I'm pretty certain the same (or very similar) motherboard is used in the entire line. The notable differences would be an optional webcam, a memory card reader, and a different wireless chipset (probably Broadcom based).


Chipset - http://downloadmirror.intel.com/16023/a08/infinst_autol.exe
Video - http://downloadmirror.intel.com/17178/a08/win2k_xp1437.exe
AHCI driver - http://downloadmirror.intel.com/17269/eng/f6flpy3287.zip
    This is the driver that is needed during XP setup. Put it on a floppy disk and press F6 when prompted. Pick the
     ICH8 Mobile option from the menu. If you're doing a driver slipstream onto your XP CD, this is also the driver
     that you'll need. If you're installing with the SATA option set to compatibility mode, you don't need this.
AHCI Drivers/Utility- http://downloadmirror.intel.com/17268/eng/iata87enu.exe
Wired Network - ftp://202.65.194.211/cn/nic/Driver_5687_XP_0520.zip
Wireless Network - xp32-7.4.2.75.zip (mirror).
Audio - CompaqC751nrAudioXP32.zip (mirror)
     There is a file called kb888111xpsp2.exe in the zip that you need in order for the Audio Devices to be
     detected properly. Run it first, then the drivers in the zip above will work. The patch might be
     unnecessary with XP Service Pack 3 (it supposedly has the UAA patch built-in), in which case you'd just need
     the driver.
Modem - Download from Windows Update (The driver from here should work as well if forced via Device Manager)
Quick Launch Buttons - ftp://ftp.hp.com/pub/softlib/software8/COL18360/ch-47422-1/sp33258.exe
Alps Touchpad  - http://cdgenp01.csd.toshiba.com/content/support/downloads/driver_touchpad_os2008204a.exe

Bios F.34 - ftp://ftp.hp.com/pub/softpaq/sp41001-41500/sp41279.exe


Other useful tips:
RMClock (http://cpu.rightmark.org/products/rmclock.shtml) works great for monitoring temperatures and SpeedStep settings. You can get a realtime display of what freq. the CPU is currently running at, and also make manual SpeedStep profiles. I was able to reduce the voltage on the Max Speed from 1.25 to 1.1 with no problems and reduced the max temps by quite a bit.

If youre installing XP from a normal CD, you'll run into trouble with setup not detecting the hard drive. Go into the BIOS and change the AHCI mode to the backwards-compatibility option. Now XP can install successfully.  Otherwise you can create a custom XP CD with the Intel drivers slipstreamed into it.
If you're feeling adventurous and want to get AHCI working after the fact, I was able to do so by following these instructions: link. Download the "patch only" version, and grab the latest AHCI drivers from above. Follow the instructions for modifying the patch, shutdown, switch to AHCI mode in the BIOS, and XP should redetect some hardware on bootup. You're now running in AHCI mode and can install the Intel Monitor software if you'd like.


 

Credit to ZzBloopzZ (http://forums.slickdeals.net/showpost.php?p=10535807&postcount=150) for the start of this list and some updates

 

Changelog:

*4/26/08: Added new customized audio driver, reference to Toshiba modem driver, much newer/better ALPS touchpad driver
*5/3: Whoops - apparently Google Apps for domains has a bandwidth limit, and this page is more popular than I thought. I've mirrored the files I had locally here: http://webpages.charter.net/mmooglemirror/
* 5/12: Added a newer wireless driver, note about MS UAA patch, XP AHCI setup tip
* 6/23: New AHCI, video drivers
* 6/27: New BIOS
* 7/13: Chipset, Wired driver
* 2/10/09: Video , AHCI driver and utility, BIOS, touchpad updates