You are right. When you try to install Windows XP on a dv2519tu Notebook, it does not detect the Hard drive. The reason is the dv2519tu Notebook is shipped with a SATA drive and a Windows XP disk does not include the SATA drivers by default. So, it will fail to detect the Hard drive and you will get a message that the Hard drive is not found.
You need to install the SATA drivers provided by HP at the following link and to do this, you need a USB Floppy drive as this Notebook does not have a Floppy drive built-in.
Get the SATA drivers and the steps to install it at the following HP website:
*h10025.www1.hp.com/ewfrf/wc/generi...softwareitem=ob-39535-1&jumpid=reg_R1002_USEN
You will then be able to install Windows XP. If you do not find a floppy drive, you can still go ahead and include the SATA drivers into a Windows XP installation disk. You will need the original Windows XP disk, a blank disk, a free utility named NLite and the SATA drivers from the manufacturer.
You can download the NLite from:
*home.midmaine.com/~nlite/nlite/nLite-1.4.5.installer.exe
You will find the steps to integrate the SATA drivers into the Windows XP installation disk at the following NLite website:
*www.nliteos.com/guide/
Let me know if this helps you or you require any further clarifications.