Laptop Problems

Im looking at these two laptops and having a hard time knowing what is the difference and which one is the better buy thanks.
hp pavilion dv6885se is
below.
Enhanced Intel® Centrino® processor technology with interrelated Intel® Core™2 Duo mobile processor T8100, Intel® PRO/Wireless 4965AGN network connection (802.11a/b/g/n) and extended battery life capability
3GB DDR2 memory for multitasking power; 800MHz frontside bus, 3MB L2 cache and 2.1GHz processor speed
Multiformat DVD±RW/CD-RW drive with double-layer support records up to 8.5GB of data or 4 hours of video using compatible media; also supports LightScribe direct-disc labels using compatible LightScribe media
The next-generation Intel® Core™2 Duo processor is based on the innovative Intel® Core™ microarchitecture, so it runs faster and is more energy-efficient for cooler, quieter operation
15.4″ WXGA high-definition widescreen display with BrightView technology and 1280 x 800 resolution
250GB Serial ATA hard drive (5400 rpm)
hp pavillion dv6875se is
below.
Enhanced Intel® Centrino® processor technology with interrelated Intel® Core™2 Duo mobile processor T5550, Intel® PRO/Wireless 3945ABG network connection (802.11a/b/g) and extended battery life capability
3GB DDR2 memory for multitasking power; 667MHz frontside bus, 2MB L2 cache and 1.83GHz processor speed
Multiformat DVD±RW/CD-RW drive with double-layer support records up to 8.5GB of data or 4 hours of video using compatible media; also supports LightScribe direct-disc labels using compatible LightScribe media
The next-generation Intel® Core™2 Duo processor is based on the innovative Intel® Core™ microarchitecture, so it runs faster and is more energy-efficient for cooler, quieter operation
15.4″ WXGA high-definition widescreen display with BrightView technology and 1280 x 800 resolution
320GB Serial ATA hard drive (5400 rpm
also why is the dv885se more expensive then the dv875se why do thank that is.