Radeon RX 6400 vs R9 255 OEM

Primary details

GPU architecture, market segment, value for money and other general parameters compared.

Place in the rankingnot rated277
Place by popularitynot in top-100100
Cost-effectiveness evaluationno data53.23
Power efficiencyno data25.70
ArchitectureGCN 1.0 (2011−2020)RDNA 2.0 (2020−2024)
GPU code nameCape VerdeNavi 24
Market segmentDesktopDesktop
Release date21 December 2013 (10 years ago)19 January 2022 (2 years ago)
Launch price (MSRP)no data$159

Cost-effectiveness evaluation

Performance to price ratio. The higher, the better.

no data

Detailed specifications

General parameters such as number of shaders, GPU core base clock and boost clock speeds, manufacturing process, texturing and calculation speed. Note that power consumption of some graphics cards can well exceed their nominal TDP, especially when overclocked.

Pipelines / CUDA cores512768
Core clock speed900 MHz1923 MHz
Boost clock speed930 MHz2321 MHz
Number of transistors1,500 million5,400 million
Manufacturing process technology28 nm6 nm
Power consumption (TDP)65 Watt53 Watt
Texture fill rate29.76111.4
Floating-point processing power0.9523 TFLOPS3.565 TFLOPS
ROPs1632
TMUs3248
Ray Tracing Coresno data12

Form factor & compatibility

Information on compatibility with other computer components. Useful when choosing a future computer configuration or upgrading an existing one. For desktop graphics cards it's interface and bus (motherboard compatibility), additional power connectors (power supply compatibility).

InterfacePCIe 3.0 x16PCIe 4.0 x4
Width2-slot1-slot
Supplementary power connectors1x 6-pinNone

VRAM capacity and type

Parameters of VRAM installed: its type, size, bus, clock and resulting bandwidth. Integrated GPUs have no dedicated video RAM and use a shared part of system RAM.

Memory typeGDDR5GDDR6
Maximum RAM amount2 GB4 GB
Memory bus width128 Bit64 Bit
Memory clock speed1150 MHz2000 MHz
Memory bandwidth73.6 GB/s128.0 GB/s

Connectivity and outputs

Types and number of video connectors present on the reviewed GPUs. As a rule, data in this section is precise only for desktop reference ones (so-called Founders Edition for NVIDIA chips). OEM manufacturers may change the number and type of output ports, while for notebook cards availability of certain video outputs ports depends on the laptop model rather than on the card itself.

Display ConnectorsNo outputs1x HDMI 2.1, 1x DisplayPort 1.4a
HDMI-+

API compatibility

List of supported 3D and general-purpose computing APIs, including their specific versions.

DirectX12 (11_1)12 Ultimate (12_2)
Shader Model5.16.7
OpenGL4.64.6
OpenCL1.22.2
Vulkan1.2.1311.3

Pros & cons summary


Recency 21 December 2013 19 January 2022
Maximum RAM amount 2 GB 4 GB
Chip lithography 28 nm 6 nm
Power consumption (TDP) 65 Watt 53 Watt

RX 6400 has an age advantage of 8 years, a 100% higher maximum VRAM amount, a 366.7% more advanced lithography process, and 22.6% lower power consumption.

We couldn't decide between Radeon R9 255 OEM and Radeon RX 6400. We've got no test results to judge.


Should you still have questions concerning choice between the reviewed GPUs, ask them in Comments section, and we shall answer.

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AMD Radeon R9 255 OEM
Radeon R9 255 OEM
AMD Radeon RX 6400
Radeon RX 6400

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Community ratings

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Questions & comments

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