odd problem involving boot discs and ###ne

[GuNd j]

I did get the boot disc from there, and it works a charm, but my point is that it won't boot on the ###ne directly, i need to swap it with another game (copy or original, so it isn't the modchip). Same goes for copies of Gameshark and Xploder which i burnt. And swapping kind of defeats the point of making a boot disc don't it?

But this same copy will boot in my older PSX SCPH-1002 directly. So im confused on why, see what i mean?

Ohh and all these images were the right region, so they don't not boot because of the territorial lockout.

Thanx for the help anyway.