In a dreamcast there are 2 "OS's" that can be used, one is the DC-OS(not the actual name for it) and the other is WinCE, I hesitate using the term OS to refer to each but I felt it's easier to understand this way. I'm not positive which one uses IP.BIN but the great thing is that either one can boot using ip.bin. This is the reason why some games won't have an IP.bin in them, they use the boot method that doesn't use ip.bin. Because the Dreamcast also uses/supports WinCE there are ppl who have made Linux emulators for the dreamcast, and emulators for many other consoles/computers/etc, they just code it in windowsCE and trouble shoot as needed.
The thing to realize that it doesnt' matter if a game has an IP.bin or not before you try and make it self booting. As long as you use the selfboot tutorial at the top of the forum any game you make this way should play in a dreamcast, this is the method I used to burn all the burnt games I have and they all still work to this day. Of course remember that cr-rw's won't work in a dreamcast without modifying your dreamcast in a very bad way, but the reason for using a cd-rw in this forum is so it burns as a selfboot then you can make a disk image out of it.
I'm one of the unlucky ones that the games that I do have either aren't compatible yet or I have the actual game cd so I can't do anything with them. For those wondering, the DC cd's use it's own type of file system called GD-ROM, it holds 1 gig of info on 1 cd and is unreadable on a regular cd-rom.
If you want to know how games are ripped off of gd-cd's then do a search .. i'm not gona explain it here.
Now.. there are alot of ppl wondering now .. how do they fit 1g of info on 700ish megs of cd space, well that's where ppl like echelon and the other DC rip grps were absolute genious, and i'll use Skies of Arcadia as an example since it took up 2 full GD-roms (some games didn't take up much space and didn't need to have anything special done to them). They compressed the entire cd so that it would fit on something we could burn .. then coded a real time de-compressor for the dreamcast so that the game would be decompressed as it was played allowing for the game to be kept on the same amount of cd's while allowing the the difference in size. Those who have A DC and a 2 disc version of Skies will notice a pause at combat .. this is the de-compressor at work. Absolute genius in my opinion but may account for alot of the problems we face now with chankast. Also to note is that some games were split off into 2 cd's with out compression and there was instruction on how to properly get the game going again on the second CD, I believe that Grandia 2 was part if this idea (ripper unknown), and there was a txt file saying when to save the game and resart the game using the second CD then restart the saved game to continue the game.
I did get Phantasy Star online V2 to work but I have an nvidia card and it's basically unplayable, although at certain angles I get the real screen and it looks realy nice!!
I hope any who read this can use the info in it as kind of a "ok so that's how the DC kinda works" guide. I didn't plan on getting into detail because i'm just going off the top of my head on the details from when I use to be into the DC scene 2 years ago .. I realy do hope this helps.
If any can clarify on the stuff here plz post your fix's
Ennok