How a GPU Works
A Graphics Processing Unit (GPU) is a specialized processor designed to handle multiple tasks in parallel. While originally built for rendering images and videos, GPUs are now widely used in servers, scientific computing, AI, and cloud infrastructure.
1. CPU vs GPU: Different Design Philosophies
Unlike a CPU (Central Processing Unit), which has a few powerful cores optimized for sequential tasks, a GPU has thousands of smaller cores optimized for parallel workloads.
| Feature | CPU | GPU |
|---|---|---|
| Cores | Few (4–64) | Hundreds to thousands |
| Strength | Sequential processing | Parallel processing |
| Typical Use | General computing, OS tasks | Rendering, AI, simulations, data processing |
| Latency | Low | Higher |
| Throughput | Moderate | Very high |
This parallelism makes GPUs ideal for workloads like: - AI and Machine Learning - Scientific simulations - Data analytics - High-performance rendering - Video transcoding
2. GPU Architecture Overview
A typical GPU consists of:
- Streaming Multiprocessors (SMs): Clusters of small cores that execute threads in parallel.
- Memory Controllers: Manage access to high-bandwidth VRAM (Video RAM).
- Scheduler: Distributes tasks to cores efficiently.
- PCIe Interface: Allows data transfer between CPU and GPU.
- Cooling & Power Components: Maintain performance under heavy load.
The SMs are what allow the GPU to perform thousands of calculations simultaneously.
3. The Processing Workflow
Here’s a simplified view of how a GPU processes data on a server:
-
Task Submission
The CPU sends a workload (e.g., matrix computation, rendering job) to the GPU driver. -
Data Transfer
Input data is transferred from system RAM to VRAM through the PCIe bus. -
Parallel Execution
The GPU splits the job into thousands of threads executed by SMs. -
Result Collection
Once completed, the results are sent back to system memory or stored on the GPU for further processing.
4. GPU Memory (VRAM)
GPUs use VRAM (Video RAM), which has high bandwidth compared to system memory.
This allows for fast data access but requires careful memory management, especially in multi-GPU or server environments.
| Memory Type | Typical Bandwidth | Use Case |
|---|---|---|
| GDDR6 | High | Gaming, AI inferencing |
| HBM2e | Very High | HPC, AI training, data centers |
| GDDR5 | Moderate | Entry-level workloads |
5. GPU in Servers
In server environments, GPUs are not just for graphics. They accelerate compute-intensive tasks like:
- Deep learning training (e.g., TensorFlow, PyTorch)
- Real-time rendering
- Parallel processing for analytics
- Cryptographic computations
- Virtual Desktop Infrastructure (VDI)
Many modern servers use multiple GPUs connected through: - PCIe Gen4/Gen5 - NVLink (NVIDIA) - Infinity Fabric (AMD)
This enables massive parallelism for enterprise workloads.
6. Software & Drivers
GPUs require specialized software to interact efficiently with the system:
- CUDA (NVIDIA) or ROCm (AMD) for compute acceleration
- OpenCL for vendor-agnostic workloads
- Drivers for OS and kernel integration
- Container support (e.g., NVIDIA Container Toolkit)
💡 Tip: On Linux servers, installing the correct driver version is essential for GPU stability and performance.
7. Virtualization & GPU Sharing
Modern data centers often virtualize GPUs to optimize usage:
- vGPU (Virtual GPU) allows multiple VMs to share a single physical GPU.
- SR-IOV and MIG (Multi-Instance GPU) are used to securely isolate workloads.
- Useful for VDI, AI inference, or rendering farms.
8. Monitoring & Maintenance
To keep GPUs healthy in server environments:
- Monitor temperature, power usage, and memory utilization using tools like:
nvidia-smi(NVIDIA)rocm-smi(AMD)- Use proper cooling and airflow
- Regularly update drivers and firmware
- Schedule maintenance windows for heavy workloads
9. Common Server GPU Models
| Model | VRAM | Compute Capability | Typical Use |
|---|---|---|---|
| NVIDIA A100 | 80 GB HBM2e | HPC, AI training | Data centers |
| NVIDIA L40S | 48 GB GDDR6 | Rendering, inference | Enterprise AI |
| AMD MI300X | 192 GB HBM3 | HPC, AI workloads | HPC clusters |
| NVIDIA T4 | 16 GB GDDR6 | Inference, VDI | Edge/Cloud |
10. Conclusion
A GPU is more than just a graphics card—it’s a parallel computing powerhouse.
On servers, it enables:
- Faster computation
- Energy-efficient scaling
- Advanced workloads like AI and scientific simulations
Understanding how GPUs work is the first step in optimizing your server infrastructure for modern applications.