**Core Concept Summary**
A **GPU Server** is typically a virtualized computing instance where the physical hardware (including GPUs) is abstracted and shared among multiple users via a hypervisor. It's provisioned on-demand and offers great elasticity.
A **Bare Metal Server** is a physical, single-tenant server with no underlying hypervisor. The user gets dedicated access to all hardware components, offering raw performance and full control.
**Key Differences**
* **Nature & Tenancy:**
* GPU Server: Virtual machine. Shares underlying physical resources.
* Bare Metal Server: Physical machine. Dedicated, isolated hardware.
* **Performance & Control:**
* GPU Server: Near-native performance with minimal overhead (using passthrough tech). User controls the OS.
* Bare Metal Server: Zero virtualization overhead, delivering 100% stable performance. User has hardware-level control (can customize kernel, firmware, etc.).
* **Provisioning & Billing:**
* GPU Server: Rapid provisioning (minutes). Flexible pay-as-you-go or subscription billing.
* Bare Metal Server: Longer provisioning (hours). Primarily subscription-based.
* **Isolation & Compliance:**
* GPU Server: Logical, multi-tenant isolation. Potential for "noisy neighbor" effects.
* Bare Metal Server: Physical isolation. Ideal for strict security and compliance requirements.
* **Operational Management:**
* GPU Server: Lower ops complexity. Provider manages hardware.
* Bare Metal Server: Higher ops complexity. User is more responsible for hardware awareness.
**How to Choose?**
**Choose a GPU Server if:**
- Your workloads are elastic, batch-oriented, or need to scale quickly (e.g., AI training, rendering).
- You prioritize agility and cost efficiency with pay-as-you-go models.
- Slight virtualization overhead is acceptable for your applications.
**Choose a Bare Metal Server if:**
- You require maximum, predictable performance and lowest latency (e.g., HPC, core databases, HFT).
- You need full hardware control for custom kernels, specific virtualization stacks, or licensing.
- Your compliance mandates physical isolation.
- You are running performance-sensitive legacy applications.
**Convergence: GPU Bare Metal Servers**
Many providers now offer "Bare Metal Servers with GPUs," combining the dedicated performance of bare metal with powerful GPU configurations (like 8x H100 with NVLink). This is ideal for extreme-performance workloads needing both hardware isolation and full control.
