| Aspect | CoD4x v2.3f Client | Vanilla 1.7/1.8 Client | |--------|--------------------|------------------------| | Can join CoD4x servers | ✅ Yes | ❌ No | | Can join stock 1.7/1.8 servers | ❌ No (unless server also runs CoD4x) | ✅ Yes | | Server browser reliability | Excellent (built-in master) | Poor (needs fix) | | Performance / FPS | Uncapped, smoother | Capped at 125/250, stutter possible | | Anti-cheat | Basic | None (PB dead) |

Older versions of COD4X (v1.x) used a different network protocol than v2ff. If a server is running an old version of the COD4X server binary (e.g., v1.8), a client using v2ff might see "Protocol Mismatch" or "Client version not allowed."

If you run a server and want to offer "Server Free" alongside COD4X v2ff compatibility:

Add these lines to your server.cfg:

// Disable XP and progression
set g_xp 0
set scr_game_perks 0
set scr_game_hardpoints 0
set scr_game_allow_finalkillcam 0
// Optional: Unlock all weapons via mod
// (Not strictly necessary if g_xp 0 works, but some mods need it)
set sv_mod "mods/ServerFreeMod"
// Allow COD4X v2ff clients
set sv_client_connect "1"
set sv_allowed_clients "cod4x"

Restart the server. Players using COD4X v2ff will connect without protocol errors, and all weapons will be available.

Play 50-player Ground War or 64-player custom zombie mods without crashing. Standard COD4 servers become unstable above 32 players.