Radeon HD 4855 and Radeon HD 4870 X2 - video card comparison
Radeon HD 4855
Radeon HD 4870 X2
Architecture
TeraScale (2005−2013)
TeraScale (2005−2013)
GPU code name
RV770
R700
Market segment
Desktop
Desktop
Release date
January 2010
August 2008
Interface
PCIe 2.0 x16
PCIe 2.0 x16
Supplementary power connectors
1x 6-pin
1x 6-pin + 1x 8-pin
Core clock speed
575 MHz
700 MHz
Floating-point performance
736.0 gflops
2x 1,120.0 gflops
Manufacturing process technology
55 nm
55 nm
Number of transistors
956 million
956 million
Pipelines / CUDA cores
640
800
Power consumption (TDP)
110 Watt
286 Watt
Texture fill rate
18.40
28.00
Memory type
GDDR5
GDDR5
Maximum RAM amount
512 MB
1 GB
Memory bus width
256 Bit
256 Bit
Memory clock speed
3600 MHz
3600 MHz
Memory bandwidth
115.2 GB/s
115.2 GB/s
Display Connectors
1x DVI, 1x HDMI, 1x VGA
2x DVI, 1x S-Video
HDMI
+
-
DirectX
10.1 (10_1)
10.1 (10_1)
OpenCL
1.1
1.1
OpenGL
3.3
3.3
Shader Model
4.1
4.1
Vulkan
N/A
N/A