Radeon R9 390X vs Radeon RX 6400
Performance-wise the Radeon RX 6400 is out front, significantly faster, roughly 20% up on the Radeon R9 390X. It is also the stronger value pick here, so it's the easy recommendation if your budget allows.
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.
Price & Value
Right now the Radeon RX 6400 starts at $265 EUR against $364 EUR for the Radeon R9 390X. Because it's both faster and competitively priced, the Radeon RX 6400 wins on performance-per-dollar by about 65%. The Radeon RX 6400 still sits about $106 EUR above its $159 EUR MSRP. The Radeon R9 390X is trading below its $429 EUR MSRP — a genuine deal.
Power & Efficiency
The Radeon RX 6400 sips power at 53W next to the Radeon R9 390X's 275W, and still leads on performance-per-watt — quieter, cooler, and gentler on your PSU. Its more modern RDNA 2 architecture on a TSMC N6 process is part of why it does more with each watt.
VRAM & Future-Proofing
The Radeon R9 390X's 8GB (vs 4GB on the Radeon RX 6400) gives it more room for 4K textures and memory-hungry creative or AI workloads. 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 all-round winner here — it's faster and the better value, so buy it if it fits your budget. Only consider the Radeon R9 390X if you find it at a steep discount.
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?
Is the Radeon R9 390X worth the extra $99 EUR over the Radeon RX 6400?
Does the Radeon R9 390X have enough VRAM advantage to matter?
Which should you buy: Radeon R9 390X or Radeon RX 6400?
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 |