Mobility Radeon HD 3870 X2 and GeForce GT 645M - video card comparison
Mobility Radeon HD 3870 X2
GeForce GT 645M
Architecture
RV6xx (2007−2010)
Kepler (2012−2018)
GPU code name
M88-XT CF
N13P-GS
Market segment
Laptop
Laptop
Release date
September 2008
March 2012
Bus support
-
PCI Express 2.0, PCI Express 3.0
Interface
PCIe 2.0 x16
PCIe 3.0 x16
Core clock speed
660 MHz
Up to 710 MHz
CUDA cores
-
384
Floating-point performance
2x 422.4 gflops
544.5 gflops
Manufacturing process technology
55 nm
28 nm
Number of transistors
666 million
1,270 million
Pipelines / CUDA cores
640
384
Power consumption (TDP)
110 Watt
32 Watt
Texture fill rate
10.56
22.7 billion/sec
Memory type
GDDR3
DDR3\GDDR5
Maximum RAM amount
512 MB
2 GB
Memory bus width
256 Bit
128bit
Memory clock speed
850 MHz
1800 MHz
Memory bandwidth
54.4 GB/s
Up to 64.0 GB/s
Shared memory
-
-
Display Connectors
No outputs
No outputs
HDMI
-
+
HDCP
-
+
Maximum VGA resolution
-
Up to 2048x1536
DirectX
10.1 (10_1)
12 API
CUDA
-
+
OpenCL
N/A
1.1
OpenGL
3.3
4.5
Shader Model
4.1
5.1
Vulkan
N/A
1.1.126
3D Blu-Ray
-
+
Optimus
-
+