Could you ask this question every day? It is
THE MOST IMPORTANT OVERLOOKED ASPECT
of building a gaming pc.
Without your motherboard specs, I would have to guess;
Prebuilt intell rig; 44 months to doom.
Prebuilt AMD rig; 39 months to doom.
O.E.M intel rig; 60 months doom
O.E.M. AMD 45 months doom.
Homebuilt , quality parts (asus)
intel 90 months
AMD 55 months.
Homebuilt (MSI)
See worst case scenario's.
Homebuilt (gigabyte )
see asus ,+ 7 % ongoing critical hit fail chance.
Homebuilt (Asrock)
see asus, less frills ,+5 % later critical hit chance, if critical hit missed
longevity will ensure redundancy.