They have taken off the 128M special, and 256M special offer is the default now.
I ended up calling and they we a little hazy about the actual, but after I told the CSR about the deal he agreed to do it, and they also waved the shipping fee since online it was free.
Don't buy it with the special offer on the ram because they will not honor the rebate that way.
Also yes it is standard ATX, but the case is a dell, so if its anything like the rest of their machines, the case is fairly specific to the motherboard and options.
Marc