Int18 network boot and ASUS A7SC

Friends,

I am in Chimoio, Mocambique, on a v e r y s l o w internet connection working for a NGO as a volunteer.

I am building a thin client solution in Edubuntu Linux and need to boot over the network using computers with ASUS A7SC with SiS900 PCI Fast Ethernet to get to the server.

Bios provides the option called Int18 which I thought means the ability to boot over the network.

I get the message "boot disk failure - insert system disk".

With the hard drive connected this computer works just fine and I am actually sing it to write this message.

This works great from my Compaq Armada M700 using the F12 option. Should be no network configuration problem etc. everything is in the same classroom.

I would appreciate help with this - it is a very cheap solution for these dirtpoor schools I am working with.

Best regards

RolfJ