If you are interested in using this machine as a server, you might look for a way to increase the disk size, since it usually comes equipped with a 2 GB disk.
The easiest way to upgrade is by using an MSATA SSD. I tested this one: Dogfish MSATA SSD 120GB. It has TRIM, S.M.A.R.T., ECC, and bad block detection. Comes with a 3 years warranty and the performance is good enough for the S900 (around 500 MB/s). No cables, low power, and plug&play.
But if you already have a 2.5" SATA drive, then know that you have the option to add it to your S900. You need a SATA cable (easy) but for the power, you'll need an adapter from floppy drive to SATA that looks like this:
It's not the cheapest at 8€ (for a pack of two), but if you already have the disk then it is less expensive than buying the MSATA SSD.
Here's the layout of the motherboard.