Radeon RX 6900 XTX vs GeForce GTX 660

Primary details

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

Place in the ranking437not rated
Place by popularity58not in top-100
Cost-effectiveness evaluation3.40no data
Power efficiency5.17no data
ArchitectureKepler (2012−2018)RDNA 2.0 (2020−2024)
GPU code nameGK106Navi 21
Market segmentDesktopDesktop
Release date6 September 2012 (12 years ago)28 October 2020 (4 years ago)
Launch price (MSRP)$229 no data

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 cores9605120
Core clock speed980 MHz2075 MHz
Boost clock speed1033 MHz2435 MHz
Number of transistors2,540 million26,800 million
Manufacturing process technology28 nm7 nm
Power consumption (TDP)140 Watt330 Watt
Texture fill rate82.56779.2
Floating-point processing power1.981 TFLOPS24.93 TFLOPS
ROPs24128
TMUs80320
Ray Tracing Coresno data80

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).

Bus supportPCI Express 3.0no data
InterfacePCIe 3.0 x16PCIe 4.0 x16
Length241 mm267 mm
Height4.376" (11.1 cm)no data
Width2-slot2-slot
Supplementary power connectors1x 6-pin2x 8-pin
SLI options+-

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 GB16 GB
Memory bus width192-bit GDDR5256 Bit
Memory clock speed6.0 GB/s2250 MHz
Memory bandwidth144.2 GB/s576.0 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 ConnectorsOne Dual Link DVI-I, One Dual Link DVI-D, One HDMI, One DisplayPort1x HDMI 2.1, 2x DisplayPort 1.4a, 1x USB Type-C
Multi monitor support4 displaysno data
HDMI++
HDCP+-
Maximum VGA resolution2048x1536no data
Audio input for HDMIInternalno data

Supported technologies

Supported technological solutions. This information will prove useful if you need some particular technology for your purposes.

3D Blu-Ray+-
3D Gaming+-
3D Vision+-

API compatibility

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

DirectX12 (11_0)12 Ultimate (12_2)
Shader Model5.16.7
OpenGL4.34.6
OpenCL1.22.1
Vulkan1.1.1261.3
CUDA+-

Pros & cons summary


Recency 6 September 2012 28 October 2020
Maximum RAM amount 2 GB 16 GB
Chip lithography 28 nm 7 nm
Power consumption (TDP) 140 Watt 330 Watt

GTX 660 has 135.7% lower power consumption.

RX 6900 XTX, on the other hand, has an age advantage of 8 years, a 700% higher maximum VRAM amount, and a 300% more advanced lithography process.

We couldn't decide between GeForce GTX 660 and Radeon RX 6900 XTX. 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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NVIDIA GeForce GTX 660
GeForce GTX 660
AMD Radeon RX 6900 XTX
Radeon RX 6900 XTX

Comparisons with similar GPUs

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Community ratings

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3.7 4264 votes

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3.2 124 votes

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Questions & comments

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