Guides
Vault Hunters Server Requirements: RAM, CPU & Performance Guide
Vault Hunters 3 spikes CPU on every vault entry. Learn the real RAM and CPU requirements by player count, why vault runs are resource-intensive, and how to keep TPS stable during runs.
Vault Hunters is one of the most server-intensive modpacks you can run. The vaults — timed dungeon instances that players drop into — generate entirely new rooms on the fly, spawn custom mobs, and resolve complex loot tables, all at the same time. If your server doesn't have enough CPU and RAM headroom, vault runs will lag out, and that's the whole point of the modpack.
This guide covers Vault Hunters 3 server requirements by player count, what makes it resource-intensive, and how to keep TPS stable when multiple players are running vaults simultaneously. For general modded server sizing, see our Modded Minecraft Server RAM Guide.
Vault Hunters 3 — Quick Specs
- Minecraft version: 1.18.2 (VH3) / 1.20.1 (Vault Hunters 1.20)
- Mod loader: Forge / NeoForge
- Mod count: ~200 mods
- Minimum RAM: 6 GB (1–2 players, solo play)
- Recommended RAM: 8–12 GB (3–8 players)
- CPU: 350–500% — more if multiple vaults run concurrently
- Storage: NVMe SSD recommended (vault rooms generate new chunks on every run)
Why Vault Hunters Is Resource-Intensive
Most modpacks stress your server through persistent automation farms and large entity counts. Vault Hunters has those too — but it adds a second pressure point that other packs don't: the vault itself.
Every time a player starts a vault run, the server generates a fresh procedural dungeon. Rooms tile together from room pools, enemies spawn with custom AI and loot tables, and the timer enforces real-time pressure. All of that happens on the same main server thread as everything else. If you have 3 players entering vaults at the same time, you're generating 3 separate dungeon spaces simultaneously — each requiring chunk generation, entity spawning, and loot resolution on a single CPU thread.
CPU pressure
- Procedural vault room generation per run
- Custom mob AI during vault encounters
- Loot table resolution for chests and bosses
- Overworld automation (Create, tech mods) running in parallel
RAM pressure
- ~200 mods loaded at startup (~3–4 GB just to boot)
- Vault dimension chunks held in memory per active run
- Player skill trees, vault progress, and item data
- Overworld chunks for players outside vaults
Vault Hunters RAM Requirements by Player Count
RAM needs scale with two things: base mod overhead (~3–4 GB to load the pack) and per-player load from active vaults and overworld chunks. These are realistic figures for consistent TPS — not the minimum to boot the server.
These figures apply to Vault Hunters 3 on 1.18.2 and the 1.20.1 port. Client RAM (for playing, not hosting) is separate — allocate 6–8 GB in your launcher for the client.
Vault Hunters CPU Requirements
CPU is where Vault Hunters gets demanding relative to its mod count. Unlike most modpacks where CPU load is driven by always-on farms and redstone, Vault Hunters adds per-vault CPU cost that doesn't exist at idle. When a player enters a vault, the server generates rooms, resolves spawns, and runs mob AI — all at once, all on the main thread.
- Solo or duo: 300–350% CPU — comfortable for 1 vault at a time with light overworld automation
- Small group (3–5): 350–450% CPU — concurrent vaults spike CPU; you need headroom
- Medium server (6–10): 450–500% CPU — multiple active vaults plus automation create sustained high load
The critical issue with Vault Hunters is that CPU load is spiky, not constant. If your server is already at 80% CPU from overworld automation, vault entry spikes will push it over and TPS drops. You need genuine headroom, not just enough to stay at 20 TPS when nobody's doing anything. For more on how CPU drives server performance, see Minecraft Server CPU vs RAM: What Actually Matters.
Avoid shared-CPU hosting for Vault Hunters. If your CPU allocation is shared with other servers on the node, vault entry spikes will hit a CPU ceiling regardless of what resources are listed on your plan. For the warning signs, see How to Tell If Your Minecraft Host Is Overselling.
Why NVMe Storage Matters for Vault Hunters
Vault Hunters generates new chunk data every time a vault starts. On a slow SATA SSD or HDD, chunk generation during vault entry creates a visible stutter — the server has to write new room data to disk while loading the vault dimension at the same time. NVMe SSDs handle this 3–5× faster.
Storage speed also affects: initial server startup (loading ~200 mods from disk), overworld chunk loading as players explore, and automated backups. If your host uses spinning-disk storage, expect slow load times and vault entry lag that no amount of RAM will fix.
Performance Tips for Vault Hunters Servers
Stagger vault entries on smaller servers
On servers with 6–8 GB RAM, three players entering vaults simultaneously is significantly harder on the server than one at a time. If your RAM and CPU are tight, staggering vault entries prevents the worst spikes.
Set a world border in the overworld
Vault Hunters players naturally explore the overworld for resources. A world border (5,000–8,000 blocks) limits the number of chunks that need to be generated and kept loaded. This frees up CPU and RAM headroom for vault runs.
Pre-generate the overworld before players join
Chunk generation during active play competes with vault runs for CPU. Pre-generating within the world border moves that cost to a one-time setup. Players then load already-generated chunks instead of triggering generation mid-session.
Control automation complexity
Vault Hunters includes Create and other tech mods. Unbounded Create contraptions and large item-processing systems add constant ticking overhead. When that overhead combines with vault-entry CPU spikes, TPS drops. Encourage players to build efficient, not maximal, automation.
Use Aikar's JVM flags with a fixed heap size
Set -Xms and -Xmx to the same value to prevent heap resizing during vault runs. Heap resizing triggers garbage collection pauses at the worst possible moment. See our JVM flags guide for the full recommended startup arguments.
How Vault Hunters Compares to Other Popular Modpacks
Vault Hunters sits in the heavy tier alongside ATM10 and RLCraft. It isn't the highest mod count, but the vault mechanics add CPU spikes that other kitchen-sink packs don't have. The comparison modpack guides above have detailed per-player breakdowns if you're deciding between packs.
What Healthy Performance Looks Like
A well-resourced Vault Hunters server should hold 20 TPS outside vaults and dip no lower than 17–18 TPS during vault entry. If you're seeing sustained drops below 15 TPS during runs, you're hitting a CPU ceiling, not a configuration problem. For how to read TPS, MSPT, and CPU metrics, see What a Healthy Minecraft Server Feels Like.
If TPS only drops during peak hours regardless of vault activity, that's a sign of an oversold host — not a Vault Hunters problem. Upgrading RAM won't fix it; only dedicated CPU resources will.
Vault Hunters Server FAQ
How much RAM does a Vault Hunters server need?
6–8 GB for 1–2 players, 8–10 GB for a small group, 10–12 GB for 6–10 players. The modpack loads ~200 mods at startup and generates vault dimensions on demand, so it needs more headroom than lighter packs.
Why does my Vault Hunters server lag during vault runs?
Vault entry triggers procedural dungeon generation, mob spawning, and loot resolution simultaneously — a CPU spike. If your server is already near CPU capacity from overworld automation, vault entry pushes it over. You need CPU headroom, not just enough to idle at 20 TPS.
Can shared hosting handle Vault Hunters?
Shared hosting with unclear CPU allocations often underperforms for Vault Hunters. The vault-entry spikes require guaranteed CPU resources. On an oversold node, those spikes will hit a ceiling and cause lag. Look for hosts that show explicit CPU percentage allocations, not "unlimited CPU" claims.
Does Vault Hunters require NVMe storage?
Recommended, not strictly required. Vault room generation writes new chunk data to disk every run. NVMe SSDs handle this 3–5× faster than SATA SSDs, reducing vault entry lag and initial pack load times.
How many players can a Vault Hunters server handle?
With 10–12 GB RAM and 400–500% dedicated CPU, you can comfortably run 6–10 players. The ceiling isn't a hard number — it depends on how many vaults run simultaneously and how heavy the overworld automation is. For player count limits in general, see our Minecraft server player count guide.
Run Vault Hunters on hardware that won't lag out your runs
BiomeHosting provides dedicated CPU allocations and NVMe storage so vault runs stay smooth, even with multiple players active. View plans built for heavy modpacks.