whatwere you trying to achieve , if I may ask ?
a Morgan x13 is somewhat hardwired to x13,
If you want to access muliplier 12.5x and below, you must cut the L10 bridge which is connected and connect the one which is open.
This will remove 8x from the multiplier, which will make it 5x.
If you then connect the 4 left L10 bridge (the last L1 bridge is taken care by the hard L10 mod), you can use your Mobo settings (Bios or witch), to adjust the multi up to 12.5x
You may want to search on Morgan for all thread on this
or go directly to
www.-oc-inside.de for the interactive painter