Simple check, since the virtual drive has been armoured since NKPatcher 8 ( 2003 ) you can use this to test if you are running a softmod or a bios replacement.
( some bios can be patched ( ironically with a modified NKPatcher ) to support the VD but that's very very very uncommon )
You can download this and stick it in your apps folder link
and run it from your apps menu, if you see your softmodded then well your softmodded, if it reboots to your dashboard then you aren't.
If you are running an early 2003 Softmod it maybe using PBL to load a BFM bios, if this is the case then it will reload the dashboard, but that's very very very uncommon now as well.
Also virtual DVD drive can be disabled when compiling NKPatcher, but I haven't seen a softmod that doesn't have it enabled as it was and still is a valuable asset to the softmod community.
( it's used to play stubborn games with long name protection off the hdd )