How to: Windows 2008 R2 + Dumb Thin Client PXE bootup

Hi

I've got a client with an old Server 2003 setup which upgraded to 2008 R2 recently. With the 2003 server they used 3rd party software to make dumb thin clients. (i.e. like an old Pentium-II's with no harddrive which directly boots up in a TS session on the 2003 server).

The new 2008 R2 server has 25 RDS calcs but how do I do the same as what they did with 2003?

So if the workstation user switch on his PC, he gets the network PXE boot, but then RDS to the main server.

Thanks in advance,