I doubt that is possible. Both 3668 n 3670 use Dell proprietary motherboard that are not compatible in form factor.  Psu not compatible either. [IMAGE] 3668 [IMAGE] 3670
Is it possible to replace the motherboard in a Dell Inspiron 3668 desktop pc with the motherboard from an Inspiron 3670 along with a i3 9100 processor as to make the Inspiron 3668 Windows 11 compatible?    Thank you
Dell Inspiron 3668 motherboard upgrade to Inspiron 3670