Yeah you can set over burn for every burn if you wanted it will only over burn if the disc image contents is more than (720000 KB) 703.125 MB that is the exact amount an 80min CD can hold before over burning so for a 870MB disc it will start to over burn as soon as it hits 703.126 MB and over burn to get the rest of the data burned to fill up the 870MB disc
Utopia is junk to be honest now it was only created before the self booting method was used later releases all use the Mil-CD/Selfbooting methods
The Dreamcast itself has plenty of exclusive games though to keep you going until you can get hold of some 99min CD-R's
Blue Stinger fits 80min CD's [Not a bad game a nice little horror game]
Grandia II (I done my own 3 disc rip for 80 min CD's) [Nothing Ripped or down sampled] Not an exclusive game just a very good one, it was later ported to PC and PS2 with lower quality FMV
Illbleed fits 80min a very very cool Horror game though you will want a guide for it, best to play unguided then go to a guide to figure it out after you have a play to get the shocks you want
Shenmue and Shenmue II (Grab the PAL version as II was only released in Japan and Europe (USA missed out with that one)) Most rips of this are on 80 min CD's and is one of the few games that really shows off the Dreamcast (Shenmue II was later released on Xbox but not the first in the series)
Sonic Adventure & Sonic Adventure 2 both ported many times on later consoles, both can be found on 80min CD rips
Record of Lodoss War (A little like Diablo) very much exclusive and fits on a 80min CD [the game name Record of Lodoss War is used over lots of console but each version is usually very different even down to the type of game]
The Ring (A very cool Horror game, though I never got that far into it as I use VGA to play my Dreamcast and this one has no VGA support)
The Thing (Love this one but you may need a guide to play it) set after the films was later ported to xbox possibly ps2 also
There are other games worthy of playing the above is just a starter
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