Comparison of Sapphire Radeon HD 6670 and GeForce GT 640M Mac

Attribute	Sapphire Radeon HD 6670 ×	GeForce GT 640M Mac ×
GPU
Release year (year)	2011	2013
Reference card	AMD Radeon HD 6670 800 MHz 1 GB	-
GPU brand	AMD	Nvidia
GPU name	Turks XT	GK107
Market	Desktop	Laptop
Clock speed (MHz)	800	745
Is dual GPU	-	-
Model	Sapphire Radeon HD 6670	GeForce GT 640M Mac
Memory
Memory (MB)	1,024	512
Memory bandwidth (GB/s)	64	40
Memory bus (bit)	128	64
Memory type	GDDR5	GDDR5
Memory clock speed (MHz)	1,000	1,250
Effective memory clock speed (MHz)	4,000	5,000
Noise and power
TDP (W)	66	32
Load power consumption (W)	220	-
Idle power consumption (W)	106	-
Raw performance
Pixel rate (GPixel/s)	6.4	5.96
Render output processors	8	8
Texture mapping units	24	32
Shading units	480	384
Floating-point performance (GFLOPS)	768	572
Compute units	6	-
Texture rate (GTexel/s)	19.2	23.84
Benchmarks
Metro: Last Light	30	-
Particle simulation (mInteraction/s)	-	69.88
T-Rex (Compubench 1.5) (frames/s)	-	0.56
Video composition (frames/s)	-	11.95
Bioshock Infinite	33	-
Face detection (mPixels/s)	5.23	6.58
T-Rex (GFXBench 3.0)	3356.86	3356.32
Manhattan (GFXBench 3.0)	2774.23	2290.86
Bitcoin mining (mHash/s)	38.55	12.55
Sky Diver Factor	88.99	-
Fire Strike Factor	10.55	-
Ocean surface simulation (frames/s)	-	226.22