N43SL boardview in .fz format, 141 KB; the r20 token most likely refers to revision 2.0 of the mainboard. A viewer such as OpenBoardView or FlexBV opens the file to show components, nets and pins so you can trace a rail, locate a shorted part or find test pads. The .fz format is common for ASUS boardviews. Nothing else about chipset or GPU is in the name. Confirm the revision printed on the PCB matches, because layouts can differ between board versions.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @pepeelectronica. Enginerys does not host this file.
How to open a .fz file
Compressed and encrypted boardview used for ASUS, ASRock and Pegatron boards.
OpenBoardView (FZ key required)FlexBVBoardViewer