Ok I finally got everything working. Here's how to dual boot XP and Vista on the HP dv2550se...
Download the Intel floppy creation utility which includes the SATA driver you'll need:
http://downloadcenter.intel.com/Detail_D...uctID=2101&DwnldID=13808&lang=eng
Make the floppy and extract the drivers, then integrate the driver on a custom XP install cd using nLite (
www.nliteos.com). There are plenty of guides on how to do this.
In Vista, right click ?Computer? and choose ?Manage?. Here you can resize your Vista partition and create a new NTFS Logical partition in the empty space. Install XP on the new partition.
When it's installed, in Windows Explorer go to Tools - Folder Options - View and choose to show hidden files and show protected operating system files. Then copy the boot folder, boot.ini, NTDETECT.COM, bootmgr and ntldr from the root of your Vista partition to the root of your XP partition.
Now download and install Microsoft's .NET Framework 2.0
http://www.microsoft.com/downloads/detai...B15C5E04F5&displaylang=en
Next download and install Vista Boot Pro:
http://www.vistabootpro.org/
Open Vista Boot Pro and make a backup of your BCD file as instructed. Now go to ?System Bootloader ?and check "Windows Vista Bootloader". In the "Install Options", choose to install to a "Specific Drive? and choose your "C" drive. Click "Install Bootloader"
Next go to "Manage OS Entries" and add an entry for XP, choosing "D" as your "Boot Drive". Click ?Apply Updates?. Now XP and Vista should be bootable. You can set which is the default to boot and how long you should have to choose an OS here too.
Next, download and install Microsoft's DirectX 9.0c.
http://filehippo.com/download_directx/
Now download and install the Intel GM965 Chipset Driver, GM965 Graphics Driver & the Matrix Storage Manager. You can get them all here (top row):
http://support.intel.com/support/graphic...025753.htm
Reboot if needs be.
Get the Marvell Ethernet Adapter driver here:
http://www.marvell.com/drivers/driverDisplay.do?dId=175&pId=6
Get the Intel Wireless Adapter driver here:
http://downloadcenter.intel.com/filter_r...rTypes=all&ProductID=2259&OSFullName=Windows*+XP+Professional&lang=eng&strOSs=44&submit=Go%21
Install the two network adapter drivers.
Next, download the Ricoh Card Reader drivers for Vista:
http://h10025.www1.hp.com/ewfrf/wc/softw...ob-53272-1&lc=en&cc=us&dlc=en&product=3439353&os=2093&lang=en
Extract them to a folder, then use the drivers in the x86 folder to install each "Base System Device" manually using Device Manager... Right click "My Computer", go to the "Hardware" tab and choose "Device Manager". Scroll down til you see the three "Base System Devices".
Right click the first "Base System Device" and choose to ?Update driver?. Choose "No, not at this time" and click next, then choose ?Install from a list or specific location? and click next. De-check ?Search removable media? and check ?Include this location in the search?. Browse to the MS folder within the x86 and install click next. Now repeat this process for the second ?Base System Device?, this time choosing the MMC folder as the search location. Now do it for the third, choosing the xD folder as the search location.
Download and install the Microsoft Universal Audio Architecture before installing the audio driver:
ftp://ftp.hp.com/pub/softpaq/sp33501-34000/sp33867.exe
Download and install this Conexant HD Audio Driver:
ftp://ftp.hp.com/pub/softpaq/sp34001-34500/sp34386.exe
Download and extract the Vista Conexant Modem drivers and run the ?Setup.exe? in the V32 folder:
http://h10025.www1.hp.com/ewfrf/wc/softw...ob-49003-1&lc=en&cc=us&dlc=en&product=3439353&os=2093&lang=en
Download and install the HP Quicklaunch Buttons:
http://h10025.www1.hp.com/ewfrf/wc/softw...ob-49029-1&lc=en&cc=us&dlc=en&product=3439353&os=228&lang=en
That should be the final missing device in Device Manager:
The Lightscribe Software and the HP Software Updater and Wireless Assistant aren't really necessary but you can get them at:
http://h10025.www1.hp.com/ewfrf/wc/softwareList?os=228&lc=en&cc=us&dlc=en&product=3439353&lang=en
Hope that helps!