And a warrior.
When the PC is Off and the Soundcard Section is On, it is not under the control of the PC, and a too high voltage (or actually current)
can go through it. It has not been prooven that it can damage the soundcard, but it gets hot at places where it should not. *When* this happens, you can see it by the laser (for the toslink (internal) connection) going off. Do *not* worry when this goes off when the PC is booting, because there it is controlling it, and no problem can be there.
This may be confusing for a few (including what the switches do), because you have the upgraded version while others have not, and which latter can be seen by the given guide and two switches being dummy. Also the switch numbering is the other way around (what is switch 1 for you is switch 5 for the others; the sequence is the other way around).
This is why for the others (actually the first batch of 20) it is the advice to always leave on the PC *if* you like to leave on the DAC. So, both on or both off. With the upgraded version you can leave on the DAC, but have to switch off the Soundcard Section. BUT, when you break it in, everything (incl. PC) has to be on, because only then the DAC (actually i2s) is really running. One difference : there is no sound going though it and this may matter somewhat (the D/A chips are idle).