Softmod and TSOP flash are two completely different things, and at some point you need to work out which you have. From your description it could be either, although a plain boot screen makes a softmod far more likely.
For now, get hold of Frosty's Rescue Disc, burn the iso image to DVD-R, then cold boot with with it in the Xbox DVD drive. It should give you a simple menu including a File Explorer to allow you to have a look at the contents of the disk, and it also provides an FTP server so you can start to transfer files to the Xbox.
In parallel, download Auto-Installer.Deluxe.v4.52. It will take a bit longer, but it contains a whole pile of useful tools. When you get it, read the manual, build the version that has DHCP support, then burn it to DVD-R.
Once you have all that done, post back. N.B., don't use AID to do anything until you've posted back and we've worked out exactly how your Xbox is modded.
This post has been edited by Heimdall: Jul 7 2010, 01:33 AM