Radeon R9 390 vs Radeon RX 6400
The Radeon RX 6400 is a big jump in performance — leading the Radeon R9 390 by roughly 20% in our performance index. The Radeon R9 390, however, delivers more performance per dollar — $98 USD cheaper.
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Radeon RX 6400 vs Radeon R9 390: In-Depth Breakdown
Performance: Radeon RX 6400 vs Radeon R9 390
The Radeon RX 6400 is significantly faster, around 20% ahead of the Radeon R9 390. Both cards sit in the same broad class, well suited to entry-level 1080p.
Price & Value
On price, expect to pay $80 USD for the Radeon R9 390 versus $178 USD for the Radeon RX 6400. Despite being slower, the Radeon R9 390 offers the better performance-per-dollar (~85% better value), so budget-focused buyers should weigh it carefully. The Radeon R9 390 is trading below its $329 USD MSRP — a genuine deal.
Power & Efficiency
The Radeon RX 6400 draws just 53W versus 275W for the Radeon R9 390, 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 390 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 390'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 390 (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 390 or Radeon RX 6400?
Choose the Radeon RX 6400 if you want the most performance and can absorb the higher price. If you're optimizing for value, the Radeon R9 390 stretches your money further for only slightly lower performance.
Frequently Asked Questions
Is the Radeon RX 6400 better than the Radeon R9 390?
Which is better for 4K gaming, the Radeon R9 390 or the Radeon RX 6400?
Is the Radeon RX 6400 worth the extra $98 USD over the Radeon R9 390?
Does the Radeon R9 390 have enough VRAM advantage to matter?
Which should you buy: Radeon R9 390 or Radeon RX 6400?
Technical Specifications Comparison
Architecture & Cores
| Specification | Radeon R9 390 | Radeon RX 6400 |
|---|---|---|
| Architecture | GCN 2.0 | RDNA 2 |
| Process Node | TSMC 28nm | TSMC N6 |
| CUDA Cores (Stream Processors / Stream Processors) | 2,560✓ | 768 |
| Ray Tracing Cores | — | 12 |
Clock Speeds
| Specification | Radeon R9 390 | Radeon RX 6400 |
|---|---|---|
| Base Clock | 1,000 MHz | 1,923 MHz✓ |
| Boost Clock | 1,000 MHz | 2,321 MHz✓ |
Memory
| Specification | Radeon R9 390 | 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 390 | 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 |