The OP is so wrong in concept so as to be almost unanswerable and I really wonder why it was asked however I will take a wild stab at it without writing a full text book.
Desktop PCs.
Chassis mostly pressed steel
Circuit board, FRP beased on glass fibre, fillers and epxy or polyester resin plus silver, lead, zinc, copper and even gold plus silicon chips.
Disk drives. mostly cast aluminium with some phenolic resin while the moving parts may be steel and any number of materials
Cases are pressed steel, ABS or PC (if transparent).
Fans, any number of materials, but often ABS, PP, nylon, aluminium or steel.
Electric motors, steel, copper, plastics.
Wires, copper and PE or PVC
Monitors
Screen, glass or PC
Case, ABS
Keys on keyboard. PBT.
Plugs and sockets, PBT, mylon, PP
Mouse is PC or ABS or PC/ABS
Notebooks, as above but only PC for screens and maybe cast aluminium for chassis and any number of materials for the case. Often PC/ABS or aluminium or even titanium of Carbon Fibre composites for fashion statement. Scratc pads are PC
I am sure I missed items and materials.
Regards
Pat
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