so basically on support.lenovo.com you have to select “machine type” rather than “as-built” to see other compatible boards :) oops !

WIN,i7-7500U,N-TPM2,SWGSYSTEM BOARDS01LV688
NOK,i7-7500U,Y-TPM2,SWGSYSTEM BOARDS01LV689
NOK,i7-7500U,N-TPM2,SWGSYSTEM BOARDS01LV690
Lenovo BDPLANAR WIN,i7-7500U,Y-TPM2,SWGSYSTEM BOARDS01LV687

It used to show a different kind of part number than just the 01LV ones, I think there is one that is like HX or something … yeah seeing this on ebay. then websearching further values finds other sites with compatibilities

compatible boards
01LV679 01AX967 01HX644
01LV687 01HX692
01LV688
01LV689
01LV690
01HX602 01HX660

compatible laptops (note people have made the t480 interchangeable too)
T470 20HDCT01WW
T470 20HES44K00
T470 20HDCTO1WW
T470 20HES99L00
T25 20K70005SG

there are a _lot_ of boards in this group and it’s hard to know how far out to go. it’s cheapest to get one without its old nvidia gpu but i’ve probably gotten used to pytorch running at a certain speed :s

my library computer session is ending