From the Docs
PJ64 1.4
"Use TLB"
Possible settings: checked or unchecked
- default setting: checked
- generally recommended setting: checked, unchecked if possible (see below)
This is another highly technical core feature, it's part of the N64 CPU, used extensively by some games (Goldeneye, Mario) and not at all by others (Zelda). If a game uses the TLB (end user can't tell this without knowing or by trial and error) then this must be enabled or the game will fail with various error messages, usually soon after boot. TLB is an option mainly because you can gain some performance by turning it off when not needed, and strangely, some games require it disabled to work.