I wasn't able to solve the prob. I'm a professional test engineer and though I'm not used to test hardware, it is very similar to testing software. In my opinion it is a problem with the Marvell connector. It seems unable to find the HDD. At this moment it is impossible to update its BIOS.
I have been checking different fora in the mean time and it seems that the videocard can also form a problem (which seems strange to me).
I have contacted asus, which was a disaster. I told them what my problem was and asked them how to solve. They replied with a vague answer on a question I didn't ask. I replied, asking the same questions again. This time I received the link to the manual, which I told them I read from front to back to front again... So I replied with the same questions again: How can I boot my splashtop... They just closed the topic. how rude
2 thaenzy: You have a very recent video card so I think there's the problem. It's not supported yet. So My estimated guess is that we have to wait for a new ASUS BIOS update which gives the proper support to all you hardware parts.
If yo ever get it to work, please tell me...