I don't see any markings on the hardware and Linux doesn't disclose much about the ELO touchscreen. However, I was able to look in the "Drivers" directory of the default HioPOS Windows XP installation and found an Elo directory and the Elo settings tool in Windows disclosed the model as a AccuTouch 2210 with Serial Controller
Note, I actually tried the proprietary Elo Linux serial 32-bit drivers for the Linux 3.x kernel and I don't remember what worked and it caused pop-up errors on boot. There's a much easier solution below. Though, IF you go that route I believe you can satisfy the Motif requirement with "sudo apt-get install libmotif-dev, but I'd recommend not using the proprietary driver.
The older model that came with Windows XP has two DDR2 PC2-4200 533 Mhz SODIMM non-ECC slots behind the touchscreen. They can hold up to 1 GB each, for a total of 2GB. The newer HioPOS appear to go up to 4GB, but I'm pretty sure this older model only goes to 2GB. 2b1af7f3a8