direct comparison under identical conditions
NVIDIA A40 48GB vs RTX 3090 Chapter 2 Local LLM Comparison
If you want a single 48GB VRAM and a server environment, you could look at the A40, and if you value component accessibility and total bandwidth, you could look at the two 3090s.
core difference
| Measure | NVIDIA A40 48GB | 2× RTX 3090 48GB (NVLink) |
|---|---|---|
| Available fast memory | 46GB | 45GB |
| Memory bandwidth | 696GB/s | 1872GB/s |
| Sustained LLM power | about 400W | about 780W |
| Korean price range (KRW) | 680–780 × KRW 10,000 | 330–440 × KRW 10,000 |
Which device suits the task?
| purpose | superior equipment | reason |
|---|---|---|
| Chat / coding | 2× RTX 3090 48GB (NVLink) | In token generation with the same model, the side with higher memory bandwidth has an advantage. |
| Documents / RAG | NVIDIA A40 48GB | The side with larger available memory provides more headroom for longer contexts and KV cache. |
| Image / video | NVIDIA A40 48GB | Let's look at generation tool compatibility and available GPU memory together. |
| Setup | 2× RTX 3090 48GB (NVLink) | Compare finished product status and initial driver·system configuration burden. |
| Power / space | NVIDIA A40 48GB | Prioritize the side with lower sustained power load. |
Local pricing
NVIDIA A40 48GB is a single GPU unit, while 2× RTX 3090 48GB (with NVLink) consists of two GPUs at a single price. When comparing, the cost of the GPU unit must include the base unit cost.