Sorry.... that was years and years ago. Google did exist then, however, and that what I used to dig up the method. You'll want to learn how to align sectors correctly (XP does not do that automatically) and it will be important to make sure your BIOS is set properly for SATA emulation or XP will not load the AHCI drivers on to a fresh XP install.
That is accomplished by setting SATA emulation to "RAID + AHCI" in some HP workstatins, or "RAID" in others (which gets the drivers for both RAID and AHCI installed in both cases). HP and Intel recommend doing that for all installs, and that is how HP ships the workstations.
My recollection is that the benefit was worth the trouble, but I moved on to W7Pro64 from XP long ago so the details will need to be found by you. I just checked.... there's still lots of information on that available out there.
I personally would use an Intel SSD so that I could use the Intel Toolbox software to manually trigger TRIM for the SSD once a month in XP.