AMD Radeon HD 6990 vs NVIDIA GeForce GTX 660 Rev. 2
GPU · Specs Compare
Graphics Card
Release Date
Mar 2011
Sep 2014
Generation
Northern Islands
GeForce 600
Type
Desktop
Desktop
Bus Interface
PCIe 2.0 x16
PCIe 3.0 x16
Clock Speeds
Memory Clock
1250 MHz
1502 MHz
Base Clock
—
980 MHz
Boost Clock
—
1032 MHz
Memory
Memory Size
2GB
2GB
Memory Type
GDDR5
GDDR5
Memory Bus
256bit
192bit
Bandwidth
160.0GB/s
144.2GB/s
Render Config
Compute Units
24
—
Shading Units
1536
960
TMUs
96
80
ROPs
32
24
L1 Cache
8 KB (per CU)
16 KB (per SMX)
L2 Cache
512 KB
384 KB
Theoretical Performance
Pixel Rate
26.56 GPixel/s
20.64 GPixel/s
Texture Rate
79.68 GTexel/s
82.56 GTexel/s
FP32 (float)
2.550 TFLOPS
1.981 TFLOPS
FP64 (double)
637.4 GFLOPS
82.56 GFLOPS
Graphics Processor
GPU Name
Antilles
GK104
GPU Variant
Antilles XT(215-0807027)
—
Architecture
TeraScale 3
Kepler
Foundry
TSMC
TSMC
Process Size
40 nm
28 nm
Transistors
2.64 billion
3.54 billion
Die Size
389 mm²
294 mm²
Board Design
TDP
375W
140W
Suggested PSU
750 W
300 W
Outputs
1x DVI4x mini-DisplayPort 1.2
2x DVI1x HDMI 1.4a1x DisplayPort 1.2
Power Connectors
2x 8-pin
1x 6-pin
Graphics Features
DirectX
11.2 (11_0)
12 (11_0)
OpenGL
4.4
4.6
OpenCL
1.2
3.0
Vulkan
N/A
1.1
Shader Model
5.0
5.1
CUDA
—
3.0
▲ Specs Compare
Data sourced from official specifications and benchmark tests.