GPU Comparison
Select up to 2 GPUs to analyze their pricing, performance, and specifications side-by-side.
Market Value Leader
Market comparison is currently pending while we verify the latest benchmarks for Radeon R9 390X and Radeon RX 6400.
The Radeon RX 6400 is significantly faster than the Radeon R9 390X, leading by roughly 20% in our performance index.
Maximum Capacity Reached. Remove a model to add another. (2/2)
Radeon RX 6400 vs Radeon R9 390X: In-Depth Breakdown
Performance: Radeon RX 6400 vs Radeon R9 390X
The Radeon RX 6400 is significantly faster, around 20% ahead of the Radeon R9 390X. Both cards sit in the same broad class, well suited to entry-level 1080p.
Power & Efficiency
The Radeon RX 6400 draws just 53W versus 275W for the Radeon R9 390X, and it also delivers more performance per watt — so it runs cooler and quieter and needs less PSU headroom. Its more modern RDNA 2 architecture on a TSMC N6 process is part of why it does more with each watt.
VRAM & Future-Proofing
With 8GB against 4GB, the Radeon R9 390X has more headroom for 4K textures and memory-hungry creative/AI tasks where the Radeon RX 6400's 4GB can fall short. The Radeon R9 390X's memory is also faster — 384 GB/s versus 128 GB/s (512-bit vs 64-bit bus) — which helps feed the GPU at 4K and with heavy textures.
Generation & Longevity
The Radeon RX 6400 is roughly 7 years newer than the Radeon R9 390X (RDNA 2 vs GCN 2.0), so it generally benefits from a more modern architecture and longer driver-support runway.
Which should you buy: Radeon R9 390X or Radeon RX 6400?
The Radeon RX 6400 is the faster card by about 20%. With live pricing limited for this pair, base your decision on the spec differences above — particularly VRAM and power draw — and check current stock before buying.
Frequently Asked Questions
Is the Radeon RX 6400 better than the Radeon R9 390X?
Which is better for 4K gaming, the Radeon R9 390X or the Radeon RX 6400?
Does the Radeon R9 390X have enough VRAM advantage to matter?
Technical Specifications Comparison
Architecture & Cores
| Specification | Radeon R9 390X | Radeon RX 6400 |
|---|---|---|
| Architecture | GCN 2.0 | RDNA 2 |
| Process Node | TSMC 28nm | TSMC N6 |
| CUDA Cores (Stream Processors / Stream Processors) | 2,816✓ | 768 |
| Ray Tracing Cores | — | 12 |
Clock Speeds
| Specification | Radeon R9 390X | Radeon RX 6400 |
|---|---|---|
| Base Clock | 1,050 MHz | 1,923 MHz✓ |
| Boost Clock | 1,050 MHz | 2,321 MHz✓ |
Memory
| Specification | Radeon R9 390X | Radeon RX 6400 |
|---|---|---|
| VRAM Capacity | 8 GB✓ | 4 GB |
| Memory Type | GDDR5 | GDDR6 |
| Memory Bus | 512-bit✓ | 64-bit |
| Memory Speed | 6 Gbps | 16 Gbps✓ |
| Bandwidth | 384 GB/s✓ | 128 GB/s |
Connectivity & Power
| Specification | Radeon R9 390X | Radeon RX 6400 |
|---|---|---|
| Interface | PCIe 3.0 x16 | PCIe 4.0 x4 |
| TDP | 275 W | 53 W✓ |
| Power Connectors | 1x 6-pin + 1x 8-pin | None |
| Released | Jun 2015 | Jan 2022 |