Instruction: Parse the product information to locate the target attribute, and then provide the extracted value of the target attribute and its source in the output, specifying None if the attribute is not present.

Input:
Product title: VisionTek Radeon R7 240 2GB DDR3 PCI Express Graphics Card (900648)
Product description: Advanced Features Made Affordable... The VisionTek Radeon R7 240 graphics card offers a perfect balance of performance, features, and affordability for the gamer seeking a complete solution. It offers support for the DIRECTX 11.2 graphics standard which offers stunning 3D visual effects, realistic lighting, and lifelike imagery. With 2GB of DDR3 memory, engine clock speed of 750MHz, award-winning Graphics Core Next (GCN) architecture, and DVI-D/VGA/HDMI outputs, the VisionTek Radeon R7 240 is big on features and light on your wallet. For peace of mind ownership, it comes backed by an industry leading lifetime warranty and free lifetime US-based technical support.
Product feature: AMD PowerTune technology for higher frame rates and automatic overclocking, AMD ZeroCore Power technology for automatic power-saving efficiency, AMD App Acceleration "co-processing" to improve performance of common computing tasks
Product brand: VisionTek
Target attributes: Video Memory Type
Answer: attribute: video memory type
value: ddr3
source: product description
attribute: video memory type
value: ddr3
source: product title