Radeon R5 M255 and GeForce GT 640M LE - video card comparison
Passmark - benchmark score Radeon R5 M255 vs GeForce GT 640M LE
Radeon R5 M255
550
GeForce GT 640M LE
720
Radeon R5 M255
GeForce GT 640M LE
Architecture
GCN (2011−2017)
Fermi / Kepler (2012)
GPU code name
Topaz Pro / Sun
N13P-LP
Market segment
Laptop
Laptop
Release date
May 2014
March 2012
Bus support
PCIe 3.0 x8
PCI Express 2.0, PCI Express 3.0
Interface
PCIe 3.0 x8
PCIe 2.0 x16
Boost clock speed
940 MHz
-
Compute units
5
-
Core clock speed
940 MHz
Up to 500 MHz
CUDA cores
-
Up to 384
Floating-point performance
721.9 gflops
384.0 gflops
Manufacturing process technology
28 nm
28 nm
Number of transistors
1,550 million
585 million
Pipelines / CUDA cores
320
384
Power consumption (TDP)
-
20 Watt
Texture fill rate
22.56
Up to 16.0 billion/sec
Memory type
DDR3
DDR3\DDR5
Maximum RAM amount
4 GB
2 GB
Memory bus width
64 Bit
128bit
Memory clock speed
1000 MHz
1800 - 4000 MHz
Memory bandwidth
16 GB/s
Up to 28.8 GB/s
Shared memory
-
-
Display Connectors
No outputs
No outputs
Eyefinity
+
-
HDMI
-
+
HDCP
-
+
Maximum VGA resolution
-
Up to 2048x1536
DirectX
DirectX® 11
12 API
CUDA
-
+
Mantle
+
-
OpenCL
Not Listed
1.1
OpenGL
4.4
4.5
Shader Model
6.3
5.1
Vulkan
-
N/A
3D Blu-Ray
-
+
AppAcceleration
+
-
DualGraphics
1
-
Enduro
-
-
HD3D
+
-
Optimus
-
+
PowerTune
+
-
Switchable graphics
1
-
TrueAudio
-
-
ZeroCore
+
-