Instruction: First, identify the target attributes from the provided list. Then, scan the product title, description, feature, and brand to extract the values associated with each target attribute. Finally, create a list of dictionaries, each containing the extracted attribute, its corresponding value, and the source where it was found.

Input:
Product title: Gateway SX2840-01 Desktop PC (Black) (Discontinued by Manufacturer)
Product description: Gateway SX2840-01 Desktop PC comes with these specs: Intel Core i3-530 Processor 2.93GHz with Intel Hyper-Threading Technology, Windows 7 Home Premium, Intel H57 Express Chipset, 6144MB DDR3 Memory, Integrated Intel Graphics Media Accelerator X4500HD Graphics, 1TB SATA Hard Drive (Green Product - variable RPM), Multi-in-1 Digital Media Card Reader, High-Definition Audio Support with 5.1-channel Audio Support, 9 - USB 2.0, Keyboard and Mouse, 12.0 lbs. | 5.4 kg (system unit only), 1 Year Parts and Labor Limited Warranty with Toll-Free Tech Support, Registration/ Limited Warranty Card, Norton Internet Security Suite 2009 Trial
Product feature: Intel Core i3 Processor 2.93GHz, 6GB DDR3 RAM, 1TB Hard Drive, Intel HD Graphics, Windows 7 Home Premium
Product brand: Gateway
Target attributes: Processor Brand
Answer: attribute: processor brand
value: intel
source: product feature
attribute: processor brand
value: intel core i3
source: product description
attribute: processor brand
value: intel core i3
source: product feature